Sirius and James Headcanon
Eleven-year old Sirius getting progressively sadder over the last few weeks of term at Hogwarts because he has loved this so much but with every day that goes by, he gets closer to going ‘home’.
Eleven-year-old James writing home to ask if his new best mate Sirius Black can come visit over break and getting the answer by owl on the last day of term. James looking at Sirius and trying to tell him but being dumb and eleven and not really ever having said anything meaningful before, even to his best mate. So he just hands Sirius the letter from his mom and it says ‘James, we live in a mansion. Tell Mr. Black he can spend as much time here as he wants.’
The asking and the answering and the handing off of the letters becoming a tradition, and the letters getting progressively less formal every year as they get to know Sirius better and his summer visits grow longer and more frequent:
Second Year: ‘Tell Sirius we’d love to have him, and if he gives enough advance warning, I’ll even run to the supermarket and get those terrible Muggle biscuits he likes so much for his welcome dinner.’ (James hated those biscuits, and he sincerely considered “forgetting” to mention it to Euphemia when Sirius popped into his mirror to say he was coming)
Third Year: ‘Well, James, for your sake, Sirius had better stop by soon because if you think you’re allowed to touch your broomstick before you two clean up the mess you made of the Godric’s Hollow cottage at Christmas hols before running away to school like a couple of cowards, you are sorely mistaken.’
Fourth Year: ‘Your father says if Padfoot doesn’t get his arse over here within the first month, he can forget about golf lessons (I don’t know what ‘golf’ is, Fleamont claims it’s some Muggle thing he offered to teach you two, but if it’s going to mess up my house all of you stupid boys will have hell to pay).’
Fifth year, James not even needing to ask, because by this time every letter that his parents send him has at least a paragraph directed at Sirius, and with two months left of school, his mom sending a note unprompted: ‘We’re renovating at home. Is Padfoot planning to sleep in your bedroom, or do we need to be careful to leave an extra guest bedroom intact? PS - tell him he has terrible taste in rooms, and I don’t care that the Ophelia Suite is his favorite, it’s hideous and the bed is lumpy, and his options are the Sunset Suite or your room.’
Sirius showing up in their fireplace holding two full trunks instead of the usual half-empty one after only a week that summer and no one needing to ask.
Everyone sitting down to Sirius’ favorite breakfast the next morning, and James having a silent fight with himself about whether or not he should whine about this blatant favoritism because
On the one hand, he hates blueberry pancakes
But on the other hand, Sirius needs his favorite food more than he does right now
But on the first hand, nobody made French Toast the day James came home
But on the second hand, he wants to make sure Sirius doesn’t feel like James begrudges him anything because he doesn’t, obviously,
But then he realizes that under normal circumstances he would complain, and more than anything else what Sirius needs right now is to know that this isn’t weird for James, this is perfectly natural because they are brothers.
So, James dramatically throws his hands in the air and wails, “BLUEBERRY, Mum? You KNOW I hate how they explode in your mouth!” and for a moment no one says anything and he’s terrified that he shouldn’t have said it, but then Sirius looks up with a shit-eating grin that splits his whole face open and he’s got about ten un-popped blueberries in between his teeth (how did he do that? Where did the pancake parts go?) and he bites down hard and the blueberry juice goes shooting in all directions and sprays James straight in the face.
And Mrs. Potter trying to look disapproving but James just looks so shocked and he’s dripping purple and it’s hilarious and Mr. Potter laughing and laughing and finally pulling himself together enough to clap a hand on Sirius’ shoulder and yell, “Way to go, son!”
Sirius looking up at him, confused and skeptical, because he doesn’t get how Mr. Potter can be proud of James for getting sprayed with blueberry juice, is this some Potter family rite of passage he doesn’t know about? But then Sirius seeing Mr. Potter looking down at him, grinning and proud and laughing his head off, and realizing that he is Mr. Potter’s son now too.