A/N: This idea came to me while I was babysitting a couple weeks ago. The Sterek baby is based off the little girl I was watching.

Stiles could hear the high-pitched squeals and low chuckles from her spot in the kitchen. The last time she'd peeked in on them, Derek and their 16-month old daughter were lying on the floor, making faces at each other.

She still couldn't believe how far she and Derek had come. From being frenemies, they'd finally gotten their heads out of their butts to realize that they were totally in love with each other. They had been together for four years, living together for two, when Stiles had gotten pregnant. Derek was ecstatic; the Hale family was expanding again. To the disappointment of the pack, Stiles and Derek had decided to wait until the birth to find out the gender of the baby. They had planned to call their son Andrew Dean (after Derek's father and Stiles' all-time favorite male character (she wouldn't be swayed, no matter how hard Derek tried to get her to change her mind)). But their child was female, thus Laura Elizabeth was born. Derek nicknamed her "Lulu", which is what his first word was since his big sister was his favorite person on the planet before she forced him to play tea party with her in a frilly pink dress. However, Stiles has her own nicknamed for their child: Buffy.

"Stiles, where the hell did you come up with 'Buffy'?" Derek had asked her one time after they'd put their daughter down for the night.

"Have you ever seen 'Buffy the Vampire Slayer'?"

"Of course I have, Stiles. You forced me to watch every episode with you."

Stiles looked smug. "I know. But Buffy is badass. Just like how our daughter will be, because she's half Hale, and half Stilinski."

"No," Derek chuckled, "I'm pretty sure she's all you. She just looks like me."

Stiles sighed, snuggling into her boyfriend's embrace. "True."

"But seriously, why Buffy?"

"Buffy is short for Elizabeth."

"No, it's not. Beth is short for Elizabeth. Buffy is just strange."

Stiles huffed. "Whatever. Monsters won't be scared of a girl named Laura. They'll run from someone named Buffy."

"But we didn't name her Buffy." Derek groaned when an elbow met his abdomen. "But you can call her Buffy, since I call her Lulu."

"Which is totally adorable, by the way," Stiles grinned, rolling a little to peck Derek on the lips. "I love you."

"I love you, too."

Stiles laughed at the memory. That's when she heard tiny footsteps coming her way. She smiled as a small black-haired and green-eyed girl hopped into the kitchen, a small blue box clutched in her hands.

"Mama," the child grinned when she spotted Stiles. She held up the box to her, stretching onto her tiptoes, then tipping when she wobbled.

Stiles caught Laura easily before the toddler hit the floor. "Now, what have we got here, Buff?"

Laura had picked up the habit of picking up anything (and everything) off the floor and bringing it to someone. It didn't matter if it was a toy, or a piece of trash, or in one embarrassing case, something she had found under Derek and Stiles' bed that she just happened plop in Scott's lap one night when he was babysitting. (I'll leave it to your imagination on what she discovered.)

Stiles set Laura back on the floor as she opened the box, but what was inside was not something she had been expecting: a diamond ring. She glanced at her daughter, who was looking at the ring with complete awe on her features.

A movement in the doorway caught Stiles' eye when Derek slowly made his way into the kitchen. He took the box from Stiles, kneeling before her.

He started to say something, but Stiles was in too much of a shock to understand it, but four words at the end of his speech were as clear as day: "Will you marry me?"

Derek had barely enough time to move their daughter out from behind him before Stiles tackled him to the floor, saying, "Yes!" over and over again.

Laura didn't know what was going on, only that her parents were overjoyed, but that didn't stop her from jumping in.

And that's how the pack found the little family two hours later, napping happily on the kitchen floor.