What gives you the right?

Isaiah has a friend who lives here in the same duplex community, he is maybe two years younger, but they play and get along nicely for the most part. 

Well, the kid is being raised by a single dad who is more then a little odd. The guy is close to forty (weird for a student housing complex), and sleeps late everyday. He has been known to tell other parents that their children are too old, mean to play with his son, so they have to go inside when his son is outside. (no one actually listened other then to tell their kids to stay out of his yard, but there are public play areas that he doesn't get to control). He plays video games constantly and just gives off this creepy weird controling vibe. He has never done or said anything that I had a problem with, its just a vibe.

Well, lately the kid, luke, and Isaiah have not been getting along very well. Luke likes to tell Isaiah that I am a bad mom and that Isaiah gets away with everything (whatever that means). Point is, that this is all most likely coming from the dad. And my question is, what does he know about what goes on in my house? The guy is never outside, and has never been in my house. So where the hell does he get off talking about our home to his kid?

I told Isaiah that when Luke starts talking like that to tell him that how we run our family is not anyone else's bussiness. I don't know how much good that will do. But this whole thing bugs me.