Prologue

A/N: Hey guys! Sorry for my little hiatus, but I was getting Writer's Blocks EVERYWHERE. So. To make up for it, I made a Gravity Falls/Steven Universe AU, where:

- Gravity Falls and Beach City exist in the same universe.

- Dipper is an older brother of Mabel. (Both are born with different moms, you'll see why.)

- Dipper is unknowingly a part-gem…

- There was a fourth/fifth Crystal Gem (I can't decide which is the right one) called Diamond, (It's my birthstone so why not. :P) who… you'll see.

(I will get shitstormed because of these circumstances so hard…)

Enjoy!

"Diamond!" – he screamed – "You don't have to do this!"

"Look, sweetheart – I made a decision." – she calmly said – "He's going to live and I'll be a part of him!"

"But, Diamond! How can I raise him alone?" – he shouted

"I'm sure you'll find someone else to help." – she said as she started she started shape-shifting.

"Sweetie, no!" – he cried as she saw her look like a womb.

"Goodbye, Thomas… Take care of him…" – she said as her final words as she disappeared and a giant cloud of smoke and dust blinded Thomas' vision. After a minute or so, the smoke disappeared, and what he saw was a small little baby with a little diamond on his left arm, and a weird birthmark on his head that reassembled the Big Dipper.

"Until I decide your full name, I'll call you Dipper." – he smiled and started crying of joy and sadness.

[1 Year Later – Beach City]

Rose was calmly sitting on the couch with Greg next to her, waiting for the moment they will see each other for the last and final time. The Gems tried to convince her to not do it, but she wanted to – no matter what, ever since their former team-mate did the same with some human in Piedmont.

Greg was pretty calm, because he knew it was going to be fine. The Crystal Gems though – especially Pearl – weren't pleased by the idea. They though a part-gem would be weaker and have no point in giving birth to.

"Gems," – Rose started – "Steven won't be made to make an advantage for the team. It's for him to live a life, like them. We and humans are different, for sure. But Steven will join them, just like Diamond's boy. Dipper is and Steven will be something extraordinary – a human being." – after that, she shape-shifted into a womb, just like her former team-mate, and struggled for a little while. – "Goodbye, fellow Gems." – she said when she poofed. What remained was a chubby, little baby with a Rose Quartz gem in his bellybutton.

"Nature can be beautiful, can it?" – Greg said as he dropped a tear from his eyes.

"No, it can't." – Pearl said with a serious, yet disappointed tone.

[1 Year Later (Once Again) – Piedmont]

Thomas was at the table, eating while his wife was at work, with his 2-year-old part-gem boy, who was wearing a long-sleeved shirt - in the middle of the summer -, his currently born daughter, who looks just like Dipper, except that she isn't a Gem. She was made with his new wife, Margaret. He was a bit down. He was trying to hide the fact that there's a Gem in the family. Even from Dipper. He explained that the diamond was a leftover piece of machinery from a surgery made to him at a very young age.

Dipper was intelligent for his age. He already talked pretty clearly. He got that from Diamond. She was the most intelligent person he's ever met. He was so intelligent that he was already in kindergarten. Ugh. He shivered every time he heard that word.

Mabel loved to be goofy, even though she was just a few months old. Even though Dipper and Mabel are two years apart, they act like twins to one-another. They always do dangerous things together, and Dipper makes sure that Mabel will not hurt herself.

Thomas was worried though. He was afraid that the other kids will start realizing that Dipper is different, and mock him. Dipper was very sensitive. At least socially. He never wanted to make friends on the playground. He had no friends until Mabel showed up.

[A FEW YEARS LATER]

Dipper at this time was 9 years old. He could've gone to school 2 years ago, but he demanded that he and Mabel had to be in the same class. Or he just used that as an excuse to not go to school alone and embarrass himself. It was mostly the first option though. At this age, Dipper became very protective over Mabel. He sometimes even let himself get beaten up to protect his sister.

This was the first day of school.

[I suck at writing these, so I'll skip on it.]

[BEACH CITY]

"Steven, don't play with that!" – Pearl shouted as she took one of her smaller swords out of the 8-year-old's hands – "It could kill you!"

"Sorry." – he said – "Amethyst said that it was a toy."

"Amethyst!" – she shouted = "Steven can get hurt from what we consider 'toys!'"

The gems still didn't get used to Steven. They wanted their Rose. They currently started taking care of him. Greg was the one who took care of him until he was 6. At other times 6 years seemed like a blink of an eye. But now, since Rose was gone, it seemed like millennia. In their eyes Steven looked like a useless little child who has no connection to Rose or Gems in any way. He didn't have any friends. He was still a little chubby. He was around 3/4th of the height of Ruby, who Steven didn't know about yet. He almost didn't know anything about Gems.

They have transformed their Temple entrance into a house for Steven to live in. He needed food, clean clothes, and sleep. They found him a weird being. He seemed completely human, but with a gem stuck to his bellybutton.

[PIEDMONT]

"Let go of her!" – Dipper jumped towards a 4th grader to let go of his sister.

"What are you gonna do about it, prick?" – the bully said – "Beat me to it? HA! Go back to your class if you want to escape without getting hurt."

A white light started appearing under his shirt around his left arm.

"I said," – Dipper started as the light got stronger – "LET HER GO!"

What happened right there was incredible. Dipper hit the guy so strongly in the face that he passed out.

"How did I do that?" – he asked himself while looking at his hands.

A/N: So, do you like my stupid crossover "idea?"

If yes, please review.

This is a very bad idea, but if you guys like it, I'll be glad to continue!