Aki- Hmm, I don't like this chapter as much as the others…it was harder to write. James is just too happy and self-assured (especially compared to middle child syndrome Albus Potter). So here you go.
1
James takes being a big brother very seriously. So he is genuinely worried when Albus gets sorted into Slytherin. He is sure his more shy, more timid younger brother, who is a Potter nonetheless, is going to get torn apart in the den of snakes….but everything works out okay and Al makes friends with the Malfoy kid, who turns out not to be that horrible, and Rose hangs out with the lot of them and James feels like a weight has lifted off his chest when after a month or so of Albus' first year everything seems to be working out okay.
And all that teasing James did to poor Al, well, that was just to toughen him up.
1.5
James is terrified at the prospect that Lily might start dating. Sure, right now, she has just gotten sorted and is only eleven, but, y'know, kids these days grow up mighty fast.
2
James loves, loves, loves Quidditch. Excluding people, he loves it more than anything else in the entire world. Even the corny stuff that everyone quotes: the adrenaline rush, the wind in his hair, the feeling of competition, and elation of victory. He made the Gryffindor Quidditch team his second year as a chaser, perhaps not the most skilled compared to all the upper years, but the captain felt that James, decently talented for his age and with a good Quidditch background, would be the most dedicated.
Plus, the captain felt a little guilty. The year before, not allowed to play, James offered to be the captain's and by extension, the team's personal assistant, so they could focus on winning and not having to deal with their laundry/ broom maintenance / returning and checking out library books/ sending letters/ retrieving snacks from the kitchen between meal times/ ect.
The captain expected to get maybe a week or two out of the kid before he quit, so he and his teammates took advantage of having a personal house elf to do their bidding.
James did everything they asked, for the entire year.
3
It's weird, and he may be the only one, but History of Magic is James' favorite school subject. Sure Professor Binns is an awfully boring drone who could put raging dragon to sleep, but once he got over that…well, the topic was awesome. Most of his peers groan about remembering dates that goblin revolts started and all James can think is that they don't get it. It's not about the dates, but the people...the events…what pushed them, how it happened, why it happened, what went wrong or right. He think this is important, more important than some of the magic they learn in other classes, as practical as Lumos or Stupefy or whatever else it might be, because that magic couldn't fix the problems between people and magical races. Only understanding could do that. James thinks he might know what he wants to do with his life…if that whole professional Quidditch thing doesn't work out.
4
Some people thought being Harry Potter's son would be terrible…y'know, always trying to live up to an expectation you can't reach. James takes a different approach. He knows no one thinks he will do all the crazy ass cool stuff his dad did, but he feels up for the challenge anyway.
5
"James, do you want to hold one of them?" Ginny asks her sons, indicating to the infant Scamander child in her arms. Harry was sitting on the couch across the room holding the other twin. They were visiting Aunt Luna a few days after she had given birth to her children. They were younger than the Weasley and Potter children. Globe-trotting naturalists Rolf and Luna Scamander took a while to settle down, but now they did, they did it fully, and Luna gave birth to twins Lorcan and Lysander within the year.
James just got a wide-eyed look and shook his head wordlessly.
Luna drifted into the room still in her dressing gown, looking a bit tired, but rather above it all. "Nargles bothering you, James?" she asks.
"No," responds Ginny for the white faced James, "He was like this for Al and Lily and all of his little cousins too. He's terrified of babies."
6
James relishes in being an older brother. He likes the job, feels fine shouldering the responsibility, and really cares about his little siblings as annoying as they sometimes get. It's a good roll to have. But sometimes he thinks he is missing out on something, not having an older brother…an older something looking out for him. Sure he had his parents, but that was different, anyone would tell you that.
But then Teddy comes around to dinner at the Potter house most days of the week…and James remembers when Teddy used to read him bedtime stories when babysitting like James then would do for Al and Lily, he remembers Teddy regaling him with repeated and well detailed tales from Hogwarts, he remembers Teddy ruffling James' hair in annoying way and teasing the mickey out of him, and tickling him until he couldn't breathe. And he thinks Teddy might, kinda, be like an older brother to him.
He wishes Teddy would think like that too.
7
Brown hair. He's not sure where in the gene pool that came from, but he's got brown hair. Sure, it has a tinge of red in it in the right light, but still. Perhaps it's a blessing in a disguise, with the abundance of Weasley redheads or how Al is always getting stopped by complete strangers who want to comment on how alike he looks to Dad. It made some people stop and talk though, like they thought something had gone one with his mom in the past, just because his hair wasn't red or black. That always made James angry, because of what it said about his mom, and what it said about him. Like suddenly he was a fraud, like he wasn't his father's son. Even though he was, and there was no doubt, in anyone's mind that actually counted. So James learned to get over it.
8
He's got dad's horrible eyesight. Perhaps the one thing that he didn't wish to have inherited. It made Quidditch a tad bit harder, having to worry about a few thin pieces of wire holding too easily breakable rectangular lenses to his eyes. But dad was great at Quidditch with glasses, so James was determined to do it too, no complaints.
9
Other than being, y'know, the Chosen One's son, he had other people to live up to. He was, after all, James Sirius Potter, and that was serious business. ("No pun intended" would say after that announcement with a cheeky grin. "Okay, okay…it was intended.) The only thing he had to live on about them were stories from his father… which were scarce and many of them secondhand. But he knows they were good friends and he knows they were legendary troublemakers and pranksters. The grandfather he never met had been a Chaser on the Gryffindor Quidditch team too. That was a nice connection.
And he knows he can't really live up to anyone, especially anyone he never met. He is not sure of what is expected of him, completely. So he uses the supplies stockpiled from Uncle George's shop with Freddie and runs havock about Hogwarts between homework and girls and Quidditch practice. And when the headmistress, Professor McGonagall, groans over having to deal with a second James Potter, he just grins.
10
James was not the only one who has noted that the last two generation of Potter men had married ginger girls. Maybe he likes fully expectations too much: Quidditch and being Harry Potter's son and a big brother and carrying on his namesakes. So he thinks that he has to fall in love with a redhead too. So he looks for one. Morgan from his class tells him that he is crazy. He ignores her. But when she comes back from the summer before sixth where with her usually mousy brown hair dyed a fake shade of reddish-auburn, he thinks that her hair is close enough.
Aki- Lorcan and Lysnader are typically depicted around the same age as the rest of the next generation characters, but JKR mentioned in this documentary about her that Luna and her husband would take a while to settle down and have children because they were gonna go off and search for animals and such, so that is where that is from.
Also, next chapter, I am making an Audrey (Percy's wife according to JKR) chapter. I say it counts as a Next Generation character.