Is OTHER wrong in the post ? POST : My wife and I are staying at her mother's house while we're shopping for a new home. 

My wife's brother is also staying at the house as he is jobless. He has mental issues and is being medicated to help control his anger. He's been mostly fine in the time we've been staying there but my wife insist that it's only because I'm there. He also has drug problems. He has pawned his PS4 4 times this past month and the MIL has brought it back from the pawn shop. No end to that cycle.

The MIL has a mild case of hoarding. There is random shit everywhere. We cleaned up the basement to make room for ourselves but goddamn, it's messy, dirty, but not horribly unlivable. 

We have numerous nieces and nephews on my side of the family. It's fairly normal when these kids are staying overnight at their grandparents or their aunt and uncle house. 

My wife and I are trying for a baby and the topic came up of whether or not we're going to allow our family to babysit our children overnight. I'm ok with my side of the family doing that, they all have kids, they're experienced and they're normal.

Her family, however, I won't allow our children to stay with them overnight (Except maybe her sister after some changes to be made). That was my firm statement to my wife. She was disappointed to hear that. 

Her mother's house is not a safe environment for children to stay, there's a drug user with mental issue staying there. It's a filthy place to stay. Her sister has a pair of dogs that I wouldn't leave young kids around without supervision, it also doesn't help when her boyfriend constantly drinks and leaves beer cans all over the place (I'm not talking 10 or so, I'm talking a garbage bag full of cans after cleaning up one time)

My wife said that it's possible that her mother can clean up, get rid of her brother and said the same for her sister. 

I believe that her mother is stuck in a cycle where she is enabling her son's drug habits (Who the fuck buys a PS4 4 times from a pawn shop?) and thinks that her house is perfectly fine. Her sister on the other hand, I can see some improvement but as I said, her family has ways to go to prove to me that they're capable of taking care of little kids.

tldr; wife's family is fucked up, I told her I won't let our future children stay with them