Nope, not an Act Your Age Parody, sorry. Just, that title was already taken, so I'm going with the alternative, which works even better. Just to be clear, this one takes place the day before Thaddeus and Thor does, and is rather - different from the rest.

Also, big thank-you to anyone and everyone who's been reviewing, especially last chapter. You're all super awesome! Anyway, on with it.

"Mo-ooom!" The cry resounded throughout the house. "You have to come quick! The boys built the largest magnifying glass ever in the backyard!"

Candace paused as she grabbed her mother's wrist. "I don't even think it has any practical benefit!"

She carried the two out to the backyard, which was vacant except for the boys and their friends looking for snacks, while Candace sat there blubbering. "How!?"

The following days was the same charade. "Come on! The boys made a statue of Perry out of socks! Socks!"

"Mamá, ¡Phineas y Ferb construyeron una machina que hacerme hablar español!"

"Look outside, they're having hoverboard races. On jetpacks!"

"Mom, Phineas and Ferb made my skin green. What do you mean, you're going color blind? How does that even happen?"

"Phineas and Ferb are in the Andromeda Galaxy."

That day, Linda stopped her daughter there. "You know, some of the things you say are a little - out there, honey."

"Exactly!" Candace pointed to a random space above her on the ceiling. "Out there is where the boys are! See, I even have some doohickey they were using to get there in my hands." Neither noticed as a beam of light hit the object through the window.

"Candace, that's a teddy bear."

"Why is it a teddy bear!?"

"My point stands. Maybe when you're older you'll understand that I have better things to do than constantly running out to see - nothing!" She took a breath to compose herself. "Come on, Candace; let's go outside and see."

Candace crossed her arms and turned to follow the woman. "If they're not in space, I'll eat my shoe."

Indeed, Candace was served grilled shoe for dinner that night.

The next day, Candace could be seen laying upside down at the foot of her bed, cell phone pressed to her ear.

"I just don't get it, Stacy. Mom's never even around to see anything they do anymore. As if it needs to be even harder to bust them! Anyway, I've gotta go..."

The teenager was interrupted by the opening of her door. "Candace," her mother began, "Dad and I have a special meeting today with the head of antiquing in the Tri-State Area, and it might run long." She sighed. "Do you think you can hold down the fort for a while? We're getting back at around dinnerti-"

"What?" Candace demanded, "You're going to be gone all day? But what about when you have to bust the boys? Whatever they're doing, it's only going to last a few hours."

She tried reasoning. "Well, if I haven't seen it yet, what makes you think I might today? Besides, your father and I have been planning this for a couple of months. It's a very prestigious event."

"Ugh," droned Candace. "But it's so boring! All you do is look at a thing and say 'Wow, this is old! How old do you think it is? I think it's a hundred years old!' And then whoever you're talking to turns around and says, 'No, see this dirt smudge? It's a hundred and four years old!' And then you sell it anyway, so what's even the point?"

Linda turned to leave, and Candace followed her down the stairs. "The point is, you are making money off of the exchange of tangible pieces of history. You won't be old enough to understand until you've spent a day in my shoes."

"Oh, I'm old enough to understand anything!" Candace insisted, as her mother pulled the sliding glass door open to the outside. "Except why the yard is empty. Yo, kids! Where's the big invention?" At this point, she had maneuvered out the door to where her brothers and their friends were sitting beneath the tree, idle.

"What do you mean?" Phineas responded. "We haven't built anything."

"Well, as long as you're behaving yourselves," agreed Linda. "Now, your father and I aren't going to be here for most of today, so Candace is in charge."

Said redhead grinned at that. "I do like being in charge."

"Glad to hear it."

Linda went inside, and seconds later, the car door could be heard shutting and the vehicle pulling out from the driveway. "Well, she doesn't waste her time," Candace remarked. "So what are you all planning on doing today that I won't be busting you for?"

"Mineral identification," Phineas explained, gesturing to whatever Baljeet was studying beside him. "Baljeet's been so involved in his recent geology project that we figured we'd give him a hand. Using an invention capable of returning rocks to the form they were in as they were being made, of course!"

"Oh, you would do that for me?" Baljeet asked, briefly looking up from his examination of two cuts of stone. Looking back down at the items in his hands, he noted, "That is so nice."

Phineas shrugged it off with a smile. "It's no problem, Baljeet. What are friends for?"

"Oh, no, I was just saying this was gneiss," the Indian boy corrected, holding one up. "But my granitude is implied."

"Okay, but I have a better idea," suggested Candace. "Instead of that, how about you..." She picked up a soccer ball that was left on the grass. "...Just play a nice, safe game of sports?"

Phineas mulled it over. "Um, I'd rather we do this. Maybe later though."

"Aw, schist."

All heads turned to Baljeet: "What?"

Baljeet held up a piece of schist. "This."

Doofenshmirtz Evil Incorporated!

"So tell me, Perry the Platypus, how do you plan on defeating me this time?" Doctor Doofenshmirtz cackled to himself. "I take your silence to mean you have no way. That, or no voice box - ah, this isn't coming out right."

He coughed into his fist so as to start over. "Now, Perry the Platypus, tremble before my heinous -Inator! It's so evil and havoc-wreaking and-"

At this point, Doofenshmirtz could see his unamused nemesis's face in the mirror he was practicing in front of. "Wow, you're here early."

Perry the Platypus, unamused by the doctor's antics, replaced the grappling hook in his hand. "Uh, I don't really have a trap for you yet, but uh..."

In an act of improvisation, Doofenshmirtz shrugged off his lab coat and tossed it in Perry's direction, allowing it to drape itself over the platypus. Effortlessly Perry lifted the edge up for him to see properly. "Yeah, that was not my most effective attempt... Eeyah!"

With that cry, Doofenshmirtz took off in the opposite direction, seeing as Perry was now allowed to give chase. He stopped when he found himself cornered, back against his completed -Inator. "Whew," he noted, feeling his sides for the familiar pockets of his lab coat. "It sure feels weird not having that thing on. Anyhow, you think you have me trapped, well, you - uh - you do, except you have me trapped against today's -Inator!"

He turned around, pressed some buttons, and tried to explain. "You see, the Doofenshmirtzes from Drusselstein are coming all the way here to the States this weekend for our annual family reunion, and seeing as Roger was always their favorite, I'm going to try to turn things around this time! Seriously, they even insist on having it over here every year, just to see how 'his' city is being run. There are only, like, two of us in this whole country, it's ridiculous! Hey, if you're not using it, can I have my lab coat back?"

Perry, after thoroughly checking the article's pockets - and finding nothing but used tissues and peanut butter stains in them - handed it back. "Oh yeah, come to papa," Doof said gratefully as he shrugged it back on. "So, how am I going to win my parents' love back, you ask? Well, since I can't do it with kickball (I'll tell you all about that some other time), my only option is to play the card that got Roger his popularity over me before either of us were even born: I will have to become... the younger brother!"

The sun came back out from behind a cloud, and through the window a rainbow could be seen forming. "Aw, crud, the weather never cooperates when I'm trying to be dramatic. You know, a good thunderstorm would be nice every once in a while, just saying!" The last line was directed out the window, accompanied by an angry fist shake. "Point is, I need to become the younger - and therefore more likeable - sibling, and since I'm too lazy to fix my Time Travel-Inator, I built this machine."

In one sweeping gesture, Doofenshmirtz showed off the invention. "The Age Switch-Inator!

"With this," he continued, turning around, "I will swap the ages of Roger and myself, effectively putting myself in a position of greater parental appeasement! I wonder if that'll make the Tri-State Area like me better as well..?"

He rubbed his chin in thought. "Well, only one way to find out. Now, to use it! First, I gotta zap myself, like so..."

Perry the Platypus refused to let him get away with it; before any damage could be done, he delivered a quick punch to the machine's barrel. Its direction swiftly changed to point towards the nearby suburbia, and the second ray fired.

"Okay, you know what? Fine. You can do whatever you want with your rocks or whatever, as long as you don't bother me. It's not like there are any adults around to bust you."

As Candace turned around to walk back inside the house, a solid yellow beam of light hit her on the back of the head.

Her body glowed white for a split second, and when it stopped, an entirely different Candace stood in front of them. "Excuse me," she snapped accusingly, "did one of you just throw something at me?"

Everyone except Phineas, who was smiling proudly, gawked at her sudden transformation to a full-fledged adult. "Candace!" Exclaimed her brother, "You had a growth spurt!"

"Growth spurt?" Candace repeated, doubtfully. "I haven't grown since seventh graaaa- wha?"

Her voice trailed off as she looked down at her much less flimsy limbs and torso. Her hands flew to her face and raked through her slightly shorter hair, astonished. Even her outfit changed.

"Okay, what's going on? This is not some normal stuff right here!"

"Oh, I think that's called - something like-" Phineas searched his mind for the word. "...Poo-ber-tee?"

"No, that's much more drawn out and awkward. This is just wrong. It looks like I'm, like, forty years old!"

Ferb squinted at his stepsister, then held up seven fingers. "Ferb says you look forty-seven," interpreted Phineas.

"Ugh, it doesn't matter; just change me back!" Candace demanded. "Bad things happen when I wear pants."

She shivered at memories of squirrels and poodles alike.

"Well, we'll see what we can do, but Baljeet-"

"Who cares about that?" Buford, who was silent the whole time, spoke up. "He's enough of a brainiac to figure it out for hisself."

Everyone was quiet. "Did - you just compliment Baljeet?" Isabella wondered.

"No; you complimented him."

"Um... Okay?"

"Well, in that case, Isabella, I highly amphibol-ate it," Baljeet quipped. "Because, you know, amphibole..."

Isabella shook her head. "No, I still don't get it. I basalt you for an explanation."

"Then I shale explain it."

"Talc you for that."

"And I will be sure to calcite my sources."

"Guys, guys, 'ou're trying too hard," Candace interrupted, "Besides, I have a little situation over here!"

"Did you say 'ore'?" Phineas noticed, and Isabella and Baljeet broke out laughing.

"Ore! Candace is in on it too!"

"Oh, yeah? Scoria!"

"Okay, are you guys going to help me or what?" Candace demanded, and Phineas explained.

"Oh, Candace, they're just trying to garnet a reaction out of you."

As smugly as Phineas's jovial nature allowed him to be, the boy held up one hand on either side of him and received two high-fours from his friends.

"Alright. Fine. If you're not going to help me, I'll just go and... try to adjust to my new life as an adult. It all happened so quickly..." Candace lamented dramatically, holding her right arm from the elbow down over her face as she walked out the gate and into the world.

Phineas blinked. "Well, she doesn't waste her time."

"I can't believe it!" Doofenshmirtz's voice was notably higher than normal. "Perry the Platypus, it worked! I feel so... energetic, and full of youthful vigor, and... hormonal?"

Doofenshmirtz's lab coat hung loosely around his shoulders in a way he was uncomfortable with. His hair was even sloppier than normal, and his limbs scrawnier. "Something is not right here."

The disconcerted doctor looked around for the mirror he was practicing in front of earlier. "By Jove!" He held both sides of the mirror with either hand. "I'm a teenaged boy again! This - is not at all what I had planned."

He turned around and thrust his hands in the air. "It's even better!

"When Ma sees me tomorrow, not only will I be the younger brother, I'll be the kid brother! Not - really sure what the advantages of that are, but it's gotta be somehow proportional, right? Ah, I should have thought of this earlier!"

Perry squinted at his nemesis; the only thing that could be worse than an experienced Doof is an experienced Doof with the body of a Gimmelshtumpian teen. He had dealt with this before, and he was still bothered by the memory.

"C'mon, dude, this is so hip! It's gonna rule tomorrow, I tells ya!"

But why did it not go as planned? Roger was in his forties. Perry's eyes widened. Somewhere in Danville, a teenager had just experienced their first forty-seventh birthday.

He parachuted off the building.

Candace held a hand to her forehead as she walked. "Man, what am I going to do now? I look like a middle-aged woman, but I have no job, no money, nowhere to be, going home's useless, and all I have for identification is a fifteen-year-old's learner permit!"

She shifted her hand to her chin. "Then again, I can vote now. Maybe I'll find an election somewhere. In fact, there's probably a lot more that I can do now! I - could - see my teachers in a grocery store, and it wouldn't be as weird. Or, maybe even..." She pulled out a hand mirror and looked for the slightest signs of wrinkles on her face; there were none. "Nah, I probably can't pass for a senior and get into the movies cheap. I'll have to think of something else."

Lost in her thoughts, Candace didn't notice the person whose shoulder she bumped into on the sidewalk. "Oh, I'm so sorry-" she began, then his face kicked into her memory.

"Up, my fault," Jeremy Johnson replied. "Didn't see you there, stranger."

Oh, he doesn't recognize me. Good, Candace couldn't help thinking in relief. "Uhuhuh, yeah, you too, I mean, I didn't see you either, in that-" She realized what she was doing and coughed into her hand. Then, making her voice sound deeper, she took a different route. "Yes, you should watch where you're going, young man. Kids these days never pay attention to their surroundings anymore."

She mumbled the last sentence as she walked away, so as to make the reaction sound more realistic. However, a skeptical smile grew on Jeremy's face, and he continued on his way to the Flynn-Fletcher house.

Phineas and Ferb looked up as the teen peered over their fence. "Alright, so, what did you guys do to Candace?"

Olive green couch cushions were strategically placed around a coffee table with a blanket draped over it. Standing on this structure was the triumphant figure of Heinz Doofenshmirtz, pumping two fists in the air and announcing, "I will take over the entire Tri-State Area!"

His face fell; he was still too old for this, and now that that animal was gone, there was no one in the apartment. "Now, what is it teenagers do again?" Wondered he, trying to remember so he could take full advantage of his new form. "Hey, I have a good idea. I'll just ask Vanessa! She would know."

"So I asked him if I could borrow the car just for a few hours, and you know what my dad said?" Vanessa was at Lacie's apartment, where the two were redoing their nail polish.

"What'd he say?"

"He said I could, just as long as I took all the chickens out of the exha-"

Vanessa was interrupted by the ringing of her cell phone. "Wait, this is him now. Sorry, I have to take this real quick..."

Heinz's voice sounded excited. "Vanessa, you'll never guess how old I am!"

Taking great care not to smudge her manicured hands, she pinched the bridge of her nose. "You know, that's not a great way to greet someone..."

"Just guess."

"Fine, how?"

"My Age Swap-Inator missed and I'm fifteen again! Isn't this rad, dude?"

Vanessa sent Lacie a look and got the sympathy she was asking for. "Okay, I'm coming over there. And I'm not a dude."

She hung up. "Sorry, I have to go. Tell your brother what I said about his comb collection."

"Okay, I'm here; now, what is going on?" Vanessa sounded stern.

Doofenshmirtz gawked. "Oh my gosh, I can't believe I have to look up to you now! Anyway, it's been like three weeks since I've been a teenager last, could you show me how it's done?"

Vanessa rolled her eyes. "This is what you made me leave Lacie's for? You know what, whatever, I'm going back."

"Hey, you can't talk to me like that. You have to listen to me because I'm - your - father. Nyeh."

The last mocking noise was accompanied by a sticking out of his tongue. "Alright, fine; if you let me borrow the car after this."

"Chickens," he reminded her.

In between mumbles, a weak "fine," escaped Vanessa. From offscreen she pulled out an electric guitar with a Union Jack on it, and began to play the beginning of a punk rock-sounding song.

If you want to relive the years of adolescence
There are certain things you should and shouldn't do
Forget the slang and clothes and culture of back then
Because the times have changed and that means so do you!

It's all about the social life and tech
Not the silly work and play from long ago!
A teenager is neurotic, cool, and conforms
But that's not nearly all you need to know..!

The music then changed to a prim, gavotte style as Vanessa continued.

It seems like an enormous oxymoron
But you must rebel and fit in at the same time.
There's always drama, but you don't seem to care much
Despite the raging conflict in your mind.

You know all the greatest sports teams
And actors, singers too
You get a job, you learn to drive, start to discover 'you'.
You're caught up on every season
Of the most popular shows.
Youre thinking about college
And that is all you need to know..!

"Oh, cool. I can totes do that," Doofenshmirtz claimed, as the song ended.

Vanessa cringed. "Are you sure?"

"Well, isn't that what I'm supposed to say?"

She rolled her eyes again, then patted him on the back. "You got it. Now, can I have the keys?"

"Sure, they're on this hook, up - here..." He jumped up and down at a nearby wall. "...That I can't seem to reach because I'm so short now."

"Shh," Vanessa scolded, reaching up to grab the keys and twirling them around her finger. "Self-consciousness goes on the inside, remember."

Perry did not know where to start looking for Doofenshmirtz's unfortunate victim, but he figured he would start at the Danville forty-seven-year-old convention. As he ducked around people complaining about their age and weight and talking about their lavish mid-life crises, he searched for anyone with distinctly different, adolescent-like mannerisms.

At one booth, they were holding a group vote for the most interesting forty-seven-year-old in Danville; a commotion had started up, and Perry could discern from the claims of those involved that there was currently a tie.

"Aaand, the final slip enters the box... What does it say?" An announcer narrated as a strikingly familiar woman placed her vote - apparently the deciding factor in the poll. "Let's see... Well, it appears our winner this year is none other than a Mister... Heinz Doofenshmirtz! Who - does not appear to be present. So, since this was a tie, the title will go instead to the tiebreaker, the last person to vote. Tell me, missus, what's your name?"

The woman took the microphone. "It's miss, fyi, and my name is Candace."

Perry's breathing shook. His Candace? That would explain the familiarity.

"Alright, Candace, and what made you pick Heinz?"

"Eh, I just chose the person with the funniest-sounding name."

"Oh - okay... Anything else you'd like to tell us, now that you're Danville's most interesting forty-seven-year-old?"

"Um, yes. Just a few hours ago I was fifteen."

Perry covered his ears as the crowd all laughed. "Yes, well, time sure does fly," the announcer said. "Everyone, give it up for Candace!"

Perry lowered his eyelids. He was going to fix this.

Candace jogged as fast as she could home, but her limbs didn't work as well as she was accustomed to. She was panting by the time she reached the gate to her backyard.

"Alright, I just elected myself the most interesting forty-seven-year-old in Danville, and I'm tired of being an adult," she demanded of the children as she pushed it opened.

"Shame," explained Phineas, "Dad really wanted to win that."

Candace blanked out, then blinked. "I need you guys to change me back."

"Done and dunite," her brother retorted, motioning to the machine he made. "Baljeet's all done with his project, so we've just been reverting random things to their state of formation all day for fun. Just let us use this on you, you'll turn back into a zygote, and hopefully in fifteen years you'll be back to normal again."

"Um." This was not the answer Candace was looking for. "No can do, that would mean you guys would all be older than me. I can't have that! I need to be older so I can bust - you - wait a minute..."

Candace looked up in epiphany. "Now I'm old enough to bust you guys myself!"

"So you know, I was just chilling out the other day, when all of the sudden this guy behind me starts rapping really, really loudly," Doofenshmirtz explained into his flip phone. "And I'm like, I can totally rap better than that, and he says to me, he says-"

He was interrupted by a force smashing through his wall. "Perry the Platypus? What are you doing here?"

Perry squinted at the item in the boy's hands, took it, and gave him a flat look; the device was not even on. "Yeah, Vanessa tried to show me how to be a good teenager, but it ain't working squat, dude."

The platypus pointed to the Age Switch-Inator. "Oh, you want to use that thing? Whatever. It don't even work."

Not feeling like heeding his nemesis's warning, Perry strutted towards the -Inator. He took aim at Candace and fired, then turned around and pointed it at Doof.

"Hey, what's the big deal? I didn't do anything to you!"

He fired the yellow beam and looked away as Doof grew thirty-two years older.

The disgruntled man looked around. "Hey, I feel totally diff- oh, look what you did. Curse you, Perry the Platypus!"

"Heeey, what?" A disappointed Candace groaned when she realized she was herself again. "I was just about to bust you..."

"Oh, you're back to normal," noted Phineas. "Well, at least you can watch us turn this mirror into its original form."

"Pyrite the laser," Isabella commanded, and Baljeet responded.

"Of course. Because, some rocks are fine, but others are..? No? Okay."

He activated their invention, whose beam reflected off the mirror and collapsed it into a pile of bolts, metal, wires, and tools.

"Wow. We really should have seen that coming," Phineas quipped. A small animal rubbed up against his leg; "Oh, there you are, Perry."

"Hm, I guess since Perry the Platypus didn't destroy this, there's no reason for me to try again. Let's see, first, one to one of those kids…"

He fired the beam, hitting Candace again. "Wait, did that press all the way? Oh well, I'll try it again." This time, the beam hit Ferb.

"Okay, and then I have to hit myself next. Three, two, one, and…" He pressed the button, and there was an explosion.

"Aw, shoot, that was the self-destruct button!"

Candace felt giddy, if not shorter. "Hey, this time I got even younger. Wait a minute, this means - aw, yeah, no more puberty for this ten-year-old!"

Everyone else looked at her suspiciously. To break the tension, Phineas turned around.

"Hey, where's Ferb?"

Vanessa Doofenshmirtz was absentmindedly sipping her coffee at Steam Noir when a tall, green-haired stranger took the seat across from her. He reminded her of someone, but this person was clearly five years older than the one she was thinking of.

"Um, do I know you?" She quirked an eyebrow at him.

"You don't recognise me?"

She rolled her eyes once more, this time playfully smiling. "C'mon, Ferb, let's get you back to my dad's. He'll know how to get you back to normal."

During the credits...

The next day, Heinz was lamenting his failure to his mother. "Come on, I made this whole -Inator for it and everything! If I could just have been the younger brother for one day, you would like me, and this could maybe be a good time!"

Mrs. Doofenshmirtz stopped and put a hand on her son's shoulder. "Heinz. I don't like you less than your brother because he's the younger sibling. I just can't stand you for who you are."

He let her walk away while he angrily processed that information. "Who I am... Why, who am I that you hate so much?"

From off screen, someone threw a red kickball in his direction; then, it hit him. "Terrible at kickball. That's what I am."

Then, a pause. "Wait, that gives me an idea! I'll call it the Kick-Inator - oh, it's going to be great!"

Yes, that song was indeed a backwards parody of "How to be a Lady" from My Fair Goalie. That is, the punk part is first, then it becomes the nicer, calmer part.

Anyway, thanks for reading! Carpe Diem! :D