We know Barrens had a dad at least, so how's the family situation with Gar'ret and Roth?
Barrens also has a mom! She's an orc and has some kind of plant job... Like a botanist or a professional gardener or maybe even an arborist.
As for Gar'ret and Roth...thats a good question.
Roth: I don't really have much of an idea of Bugbear culture in my setting, but at the same time, I don't even know if Roth is a typical example of them or not. If I need to cop-out, I can just stick with generic monk backstory and go the raised in a temple route.
Gar'ret: ehhhh who knows. Maybe he doesn't have parents and just tumbled off of a turnip cart one day, a fully grown freak. Or maybe he has an extremely mundane and boring home life as a humorous contrast to what a weirdo he is.