Amy placed the car into park in front of her apartment complex. Sheldon trailed behind her as she sprinted into the lobby and inserted her key into mailbox 314.

"I don't know why you didn't just have it sent to our place."

"Because technically this is still my place. I didn't want to risk the postman sending it back when he realized my name isn't associated with the Los Robles address."

She reached her hand into the opening. Junk mail, more junk mail, electric bill... "It's here!"

They regarded the small colorful box with trepidation.

"I don't want to wait. Let's go upstairs and do it here."

Before he had a chance to answer, she ran up the the stairs. "Amy, wait!" His long legs were no match for her enthusiasm.

With unsteady hands, she attempted to insert her key. Upon reaching the third floor landing, Sheldon bent over and rested his hands on his knees as he tried catching his breath. When his breathing was under control, he plucked the key from his fiancée's hand and unlocked the door.

She raced past him into the bathroom, dropping the envelopes along the way.

"Amy!" He sighed, picking up the forgotten envelopes and tossing them on the table, along with his messenger bag, before following her into the tiny room.

She turned the box over in her hands. It was sealed so tight that her nails were no match for the heavy-duty packing tape.

"Do you have a utility knife?"

"In my top desk drawer."

He returned moments later carrying the tool that would reveal the contents of the much-anticipated package. "Let me do it. You're too shaky. I don't want you to cut yourself."

Amy reluctantly handed it over. No sooner had he slid the blade through the tape, she yanked the box from his hands and lifted the lid. She pulled out the contents, carefully setting each item on the counter.

"I wouldn't have imagined there'd be a whole page of instructions. Maybe we better sit down," she suggested.

They sat side by side on the edge of the bed. Sheldon peered over her shoulder and read along.

"Do not eat, drink, smoke, chew gum, brush your teeth, or use mouthwash for at least 30 minutes prior to providing your sample. I'm good there. What else?" Her eyes roamed down the page. "The sample must be obtained, and the stabilization buffer added, within 30 minutes. Waiting longer than 30 minutes may decrease the yield and quality of your DNA."

"You have to produce 2 mL of saliva into the vial. I don't think I want to be in the room for that," he shuddered.

"You can wait here. I'll try thinking of something to make me salivate."

"What about this?" He proceeded to remove his shirts to reveal his muscular arms and chest.

She eyed her half-naked fiancé appreciatively. "That will do it. Stay there. I'll try to be quick."

Sheldon fluffed a pillow and lay back on the bed, running his hand along the familiar blue and yellow comforter. He hummed to himself to drown out the sound of his fiancée spitting in the next room. His eyes darted around the room impatiently. Ten minutes had passed, and Amy hadn't emerged. "Is everything okay in there?"

"I'm fine. I'm not quite at the 2 mL mark."

Five minutes later she entered the bedroom, vial in hand. Sheldon averted his eyes. While he had gotten much more comfortable with bodily fluids over the past year, the sight of that much saliva made him squeamish.

"Sorry." She snapped on the cover and set it in the box on her nightstand then lay down next to him. "I'm so excited. To think a little saliva contains enough genetic material to match segments of my DNA with segments of my relatives."

"It is exciting... for biology," he agreed.

"I took a genetics class at Harvard. It was so fascinating, I almost reconsidered my major."

"Really? You've never told me that before. What was it about it you found so fascinating?"

She sat up and turned to him. He mirrored her actions so they were eye to eye. "It's just amazing when you think about how the traits our ancestors had have been carried down from generation to generation. We learned about dominant and recessive traits through Mendel's law."

"Ah, yes... Mendel's law. The pea plant study."

"Exactly. When Mendel crossed purebred purple flower pea plants with purebred white flower pea plants, the result was not a blend of the two colors but rather all the offspring produced purple flowers. Then when he self-fertilized the new generation, the subsequent generation was a mix of purple and white flowers at a 3 to 1 ratio. Sorry, I'm getting off topic."

"Don't be. One of the things I love most about you is your scientific curiosity."

"I'm definity curious to learn more about my own DNA. Even if I never find my father, it will still have been worth it."

"This is the best idea we've heard yet. We really need to thank FlagWorshipper91 for her brilliant suggestion."

"I know, I just don't want to get my hopes up too high. The site claims they have over a million customers, but that's a very small percentage of the world's population, and even the country's population. The likelihood that my father, or a close relative on his side, signed up to have their DNA catalogued is extremely small."

"We're scientists; we can't rule it out. If this proves to be ineffective, we have other options."

"You're right. I should set up my profile and register my sample. Can I use your laptop?"

"Of course. It's on the table."

She returned with his messenger bag and slid the computer out. She assumed her earlier position with her back against the pillows as she brought up the '23 and Me' website. She entered her email, name, and birthdate then followed the prompts. She checked the 'Yes' box for the 'Share and Compare' feature, thus allowing DNA matches to see her profile and enabling the 'Relatives in Common' feature.

"Here goes nothing," she announced as she pressed the 'Register' button. "I'll mail the sample tomorrow and hope that in six to eight weeks I have some matches. I'm crossing my fingers for six."

He scooted closer to her and set the laptop on the nightstand. "I know something that will take your mind off it." He wiggled his brows suggestively.

"Now?"

"Why not? If you get lucky tonight, maybe you'll get lucky with the search." He jumped off the bed and began undulating his beckoning hips. When he crooked a finger at her, she slid off the bed to join him. He wrapped his arms around her waist, and they swayed to the tune of Darlin' that he hummed against the top of her head.

She sighed contentedly.

"I've missed you."

She raised her eyes to his. "You see me every day."

"No, I mean I've missed this. We've been so caught up in all the drama that we haven't... Well, you know."

"Had sex?"

He nodded.

"It's only been a couple of weeks."

"That's far too long." He pulled back slightly to look at her. "Someone's wearing too many clothes," he murmured.

She didn't protest when he slipped her vest over her head, followed by her blouse. He dropped his pants, kicking them aside. She shimmied out of her skirt so that the only barriers between them were her bra and their underwear. Pulling her against him again, he kissed her softly and spun them around so his back faced the bed. She wrapped her legs around his waist when he picked her up and gently dropped to the bed.

They recreated their first time together, only now they were both much more in tune to each other's needs. After weeks of practice, they knew exactly how their partner liked to be touched.

Two hours later, they lay panting. Amy rested her head on his chest, listening to his erratic heartbeat.

"It's getting late. We should go," he murmured.

"We could stay here."

"I don't have a change of clothes."

"Or do you?" She extricated herself and opened her dresser drawer. "After my birthday last year, I took the liberty of buying you some things in case of emergencies." She held up a Batman shirt, underwear, and socks.

"You know how much I admire preparedness. Now, come back here! I'm ready for round two." He growled.

A/N: 23andme is an actual company. I first heard of it a few years ago when I took a free online genetics course. While much of the information in this story is based on facts, I have taken some creative liberty to fit the story and because I have never actually used the kit myself. This is not an endorsement of the company; it's just interesting to me.