When Stiles is 7, his mother dies. He never really recovers from it, but he learns how to cover the wound and pretend to be normal, taking care of his father like his mother asked him to.
When Scott is 8 his father abandons his mother and him. The divorce is final within a year, and Scott never sets eyes on his father again.
When they are 11, Stiles' father and Scott's mother start dating. They're married not long after.
Stiles is torn because he knows his father still loves his mother, but he loves Melissa too, and that's okay. Melissa sits and talks with him, lets him cry even though he's supposed to be too old to cry, because he misses his mom and always will. She'd known his mother, and would never want to compare. "But I hope we can become a family, too," she says, and kisses him on the forehead.
Scott has a little more trouble with John. He doesn't trust grown-up men, but it is his best friend's father, the man his mother loves, the man who hasn't hurt his mother (yet, it's always yet in his mind). For Stiles' sake, and for Melissa's, Scott will play nice. But he's watchful of the Sheriff, always.
The boys get to be brothers, which is awesome.
Sonia is born before they are 13. She's an accident, and everyone knows it, and they love her because an accident is not always negative. Stiles is fascinated with the way her eyes are constantly moving, taking everything in. Scott can't get enough of listening to her babble and coo, and whenever she cries she has the whole family rushing to comfort her.
"She's going to be so spoiled," John says, stroking her hair and staring at her as she sleeps. There's no rancor in his tone, just wry humor for the future he can see coming.
Scott and Stiles are so willing to babysit that Melissa and John go out more after she's born than they did before. And with the boys at home, they both continue working full time after Melissa's maternity leave is up. "I wonder if we're taking advantage of the boys," she whispers to John one evening, when they're both home and the boys are upstairs playing video games, relieved of baby duty.
"They love their little sister," John says, rocking her slightly as she drifts off to sleep. "They let us know when they have something big going on, and we adjust. They're good boys, helping out the family."
When she starts talking, Stiles is the only one who can understand her at first. The rest of the family catches on quickly, but Stiles is always the reliable translator. He answers all her questions, "No, no snack because dinner is in a few minutes. Yes, you can use your green fork. Yes, you can have a piece of cake after dinner. No, you can't watch that show because it's not on." Even when she starts on the hard questions, Stiles answers honestly, "I don't know why some people are mean. I don't know why trees grow all crazy like that, let's look it up."
Scott is the one she runs to when she falls down and hurts herself. She falls down a lot, but most of the time she stumbles back to her feet, laughing and zooms off again. But if she's really hurt, scraped or even bleeding, she'll run to Scott, whimpering pathetically. Stiles is no help because he finds it unbearably funny to see her lips trembling and tears streaming down her cheeks. Scott doesn't overreact or laugh, just cleans the wounds, puts on her favorite bandages (alternates between purple stars or Lightning McQueen band-aids), then sits her on his knee and hugs her until she stops sniffling.
When they go out as a family, they make John and Melissa push the cart and Stiles and Scott walk with Sonia between them, each holding one of her little hands, both chasing after her when she breaks away. They develop a system, one of them runs after her and the other picks up or straightens whatever mess she might've made, because she's not doing it to be mean but that doesn't mean the workers should have to pay for her presence in their store.
One night when Sonia is three, John is working late and Melissa is off for the night, so she and Sonia kick the boys out of the living room for some mother-daughter bonding time, watching Disney old and new. (Scott says, "Come on, mom, at least watch Tangled! She knows how to stick up for herself and I don't want Sonia to think she shouldn't!") Stiles says, "Hey, I heard there's a half a body in the woods. Wanna go look for it?"