Lore says even in large Keeper families it is rare to have more than two (maybe three) sons, because females are born more often. Which isn't to say it's impossible, just uncommon. But if all six come from the same mother, and not from an arrangement like Naih'ir's, this may have some form of impact.
I have a Keeper boy who is the 2nd son of a very large family. My headcanon for him is that being male and the 2nd male at that, he is largely ignored by his mother.
But! Keepers live in small familial communities, not large tribes like Seekers, so it gives a lot of wiggle room - what is the norm in one community may not be the norm in the next. So it's entirely possible to make it so that in the community your characters come from, adoption is a pretty normal thing, and so is keeping the late mother's name, and so forth.
I have a Keeper boy who is the 2nd son of a very large family. My headcanon for him is that being male and the 2nd male at that, he is largely ignored by his mother.
But! Keepers live in small familial communities, not large tribes like Seekers, so it gives a lot of wiggle room - what is the norm in one community may not be the norm in the next. So it's entirely possible to make it so that in the community your characters come from, adoption is a pretty normal thing, and so is keeping the late mother's name, and so forth.
