OK, WHAT'S GOING ON....?

I think it's really cool that you have a friend like this. I think there is a possibility that he's gay. Your mum asking whether he was is a big indicator, I think. But it's hard to know, as I don't know him. I think you should just ask him. If he's cool with his bro being gay, he certainly wouldn't be offended if you asked if he is too. I'm straight, but if a gay guy asked me if I am gay, it wouldn't really bother me. Let us know how it turns out. Good luck, buddy!