there's your answer.
Yeah, I heard they were sheltered and not allowed to have friends.
The home schooling is fine, however, isolating your kids and not allowing them friends is not a good idea. I don't know if this contributed to things.
I know a family who home schools, but there kids still have friends through other means (sport teams, YMCA, neighborhood, etc.).
If the kids were not allowed to have friends, you have to wonder in what other ways the parents were screwing them up.