I am confused how that is any of your business.
^^^This^^^
Where's the girls dad in all of this? Or mom or family? Sounds like they need to step in and do their part. Don't take it wrong but if you showed up on my porch dealing me this situation when you're really not a direct parent to all this you'd be politely invited to get off my porch. Once
And ^^^This^^^
I see y'alls point perfectly, but if my kid was acting that way and threatening to hurt himself, I'd appreciate someone telling me. Daddy probably had no idea any of it was going on and has hopefully handled it with his son. I kind of took the OP as saying he was threatening the other kid with his son at first, but I think (and hope) I took that the wrong way.