Hikishi Masashi
I just figured because shouldn't they know the characters name in the bio and each other since part of the bio would be playing off each other... And since we don't know any of them(besides you) other than our own just figured it'd be easier this way.
Oh no, that isn't really necessary info in a bio.
I can write a short autobio without mentioning my brother or sister specifically, and still be spot on.
Maybe they could include mentioning having a sibling, but since they really just grew up in the same house, that's really all that is necessary to do in the profile.
The real profiling comes when we plot our characters in the OOC, and write our posts that describes their mental and emotional, even physical states in a dramatic detail that really etches out the minds of the characters.