These Are The People In My Neighborhood

So I have a dilemma I'm hoping you can help me with.

We have a neighbor (our front door looks down onto their condo) with QUITE a history.

First a woman lived there with her teenage son who smoked pot out front with all of his buddies almost every single day. They had crazy weekend parties where tons of family and friends would descend on their tiny two bedroom condo and spill out, drunk as skunks, onto the lawn, swearing up a storm and being really really loud. We were lucky if these weekly parties died down by 2 a.m.

There were also a lot of fights between the teenage son and his uncle, who often crashed with them. The uncle called the police on the teenage son at least three times while they were there, and one time the police knocked on our door for verification of something that had happened.

Oh, and did I mention I live in a fairly nice neighborhood? We're not used to this kind of stuff.

They moved out, to a house just around the corner (so that more family could live with them) and the woman's grown daughter moved in, with HER 4 year old daughter, who I'll call Amanda. Now the parties are only about once a month or so.

At least there has been progress.

Amanda used to visit and stay with her Grandma all of the time, so we knew her before she and her mother moved in. But despite Gabi and Amanda trying to play with each other when they both found themselves out front, all of their efforts were thwarted by Amanda's family, who would whisk her away into the house. Each and every time.

It was so strange. But based on some of the things the teenage son would say under his breath if we happened to walk by him on our way to get the mail, I knew that they didn't like us very much. I would just smile and go on my way, trying for as little contact as possible.

Well, lately there seems to have been a change of heart on their part. Which was fine at first. Gabi and Amanda became fast friends. But now I'm not so sure I WANT them to be friends.

The mother lets Amanda come over and play INSIDE our house, never having met me or my husband. That's right, NEVER met us, NEVER spoken to us, and NEVER responded back to any of my smiles or waves. Call me crazy, but there's no way in hell I would let Gabi play inside someone's house who I hadn't met before or acts like that. It makes me really uneasy to have Amanda over because of this.

They also let Amanda stand outside our house and scream for Gabi. Even late at night while I'm trying to put her to bed. Once Gabi hears Amanda calling for her, it's all over. If I don't let her out, I have to deal with my four year old body slamming the front door trying to get outside, and massive tears when we finally drag her away.

When Amanda comes over to play, she ends up ignoring Gabi and doing her own thing. I think it's because she's so distracted by toys that are different from hers. Poor Gabi tries to play with her friend, then sadly comes to tell me that her friend wants some private time, and can we do something together instead? Despite this treatment, Gabi still desperately wants to play with Amanda and have her over whenever she can.

Amanda is also always asking for food, and tries to take Gabi's things home with her.

I just... I don't know. I just am not keen on being associated with this family. I know the mother's new live-in boyfriend drinks and swears a lot, and I saw into their house one time and it was trashed. I feel like I should be a haven for this little girl, but I'm not comfortable with the way she acts (she's only five years old, but already a reflection of her environment?).

At what point do you not let kids associate with each other? Should I suck it up and let them still be friends? Or are there too many red flags?