So I got to thinking what Janner, Kalmer, and Leeli's kids would be like and their age range and so I came up with this (I couldn't fall asleep last night so it's pretty long-ish)
We can assume Janner and Sara get married so they would probably have the eldest child out of all of them. Kalmer and ??? (I'm gonna go with Galya) would probably have the second oldest child out of all of them. It would be cool if Kalmer's kids were opposite of him and his siblings, so it would be girl, girl then boy, and well this is getting confusing so I'm going to just write it differently.
Janner's 1st: 16, girl
Kalmer's 1st: 14 girl
Janner's 2nd: 14 boy
Leeli's 1st (she and Thorn would get married): 13 girl
Janner;s 3rd: 13 boy
Kalmer's 2nd: 11 girl
Leeli's 2nd: 11 boy
Janner's 4th: 11 girl
Kalmer's 3rd: 10 boy
Leeli's 3rd: 10 boy
Kalmer's 4th: 6 boy
Janner's 5th: 3 girl
Leeli's 4th: 2 boy
Janner's kids: 16 girl, 14 boy, 13 boy, 11 girl, 3 girl
Kalmer's kids: 14 girl, 11 girl, 10 boy, 6 boy
Leeli's kids: 13 girl, 11 boy, 10 boy, 2 boy
So the Wingfeather family household (or castle) just got a lot fuller.
Janner and Kalmer's 14 yr olds would probably be close cousins. Janner's 16 yr old would be the oldest of the bunch, so she would be the one who everyone goes to for help. Kalmer's 11 yr old would be more persuasive to the others when going on an adventure. Leeli's kids would form their own singing group, having inherited their mothers gift for singing (even though they don't have the same reaction she has to music). Janner's kids would want to protect all of the others, being the kids of a Throne Warden. Kalmer, Janner, and Leeli's 11 yr olds would be good friends, and would like to sneak away for adventure. Kalmer's 6 yr old would be more quiet, and would just like to read books. Janner's younger 2 girls would be the crazies out of his kids, and would be a force to reckon with, unless their older sister is around. Kalmer's boys would be chill and just go with the flow.
Grandma Nia would become a babysitter for the kids, but the kids would know not to mess with her. After all, they've seen Kalmer-THE KING- get in trouble with her, even as an adult. Artham would gladly take one of his great-nieces or nephews flying with him, making him end up as another babysitter, but he doesn't mind.
Sara would be the one who could order all of the kids all at once. All of the kids would listen to her without question 98% of the time. Nia is very proud of her.
Janner would be the one the kids would go to if they were dealing with a bully. Or if they had pretty much any question about anything at all.
Kalmer would be the one the older kids would go to whenever they wanted something to do, or if they wanted to go on an adventure.
Leeli would be the one they would all go to if they were sad about anything, or just needed comfort. Or a pet dog.
Arundelle would be the one who would read to all of the kids at night whenever they wanted a story or a poem read to them.
Nia would be Nia, so the kids would go to her for literally anything.
Artham would be the one who like I said earlier, would take the kids flying whenever they wanted. He would also be the one who would spend time with the kids, doing whatever they wanted.
Oskar would be the one who would teach the kids weird quotes, and would be the one who would find the right book for them.
Maraly would probably end up teaching the older kids (Janner's 16 yr old, Kalmer's 14 yr old, and Leeli's 13 yr old) how to throw a dagger.
Gammon would be the one none of the kids understood half the time because of the "Florid Sword" way he talks.
Aaaaaand that's what I've come up with😁
(I'm pretty sure Maraly would even teach the youngsters to throw a dagger 😂)