Is my friend’s son in danger? Do I keep quiet or speak up? ADVICE!

Okay, so I’m going to try not to make this too long. I have a best friend who has been my best friend for 7 years. We are 21 now and both have babies. The past 7 years, she hasn’t really changed much, she has always been kind of immature..she basically just won’t grow up. She is always stealing her parent’s money, stealing their expensive things and pawning it for money, getting in a fight with them and then taking her child and getting a cheap hotel room (with their money or using her last dollars she has) with her boyfriend for a few nights, (she lives with her parents), dragging her 1 year old son around everywhere even into the very late nights, getting drunk and high with her boyfriend after her son goes to bed almost every night, and she now has started stealing my money and my jewelry even though she won’t admit to it. I don’t want to bash her, I love her very, very much, but I wanted to say all this to explain how hard it is being friends with her, especially since she’s been doing this type of stuff the 7 years I’ve known her. I just want to surround myself with positive people. Her mom texts me constantly telling me how bad it is and how worried she is for her grandson’s life.

Now I’m in a very hard situation. A couple weeks ago, my friend was staying with her boyfriend (who isn’t her son’s dad, but helps out with him) and she woke up one morning to find a small bruise on her son’s nose. She asked her boyfriend about it, and he said that he probably fell down or something. A week or so later, another bruise on his nose appeared. She asked him again about it and he said that he accidentally did it. He claimed that he was playing around and pinching his nose like you would pinch a child’s cheek and it made a bruise. He also then admitting to doing the same thing the first time. I told her that I couldn’t support her choices if she stayed with him. Because 1, he lied about it the first time… why? And 2, if he was “playing around” and it made a bruise, why would he do it again if he knew it made a bruise the first time? Her first thought was that he did it because her son wouldn’t stop screaming (he hates when he cries) because she said she was half asleep when she heard screaming and found that bruise a few minutes later. But, now she says she believes him and won’t walk away and gets mad at me for not supporting her choice to stay with him. She also has a huge bruise on her for him grabbing her too hard a couple nights ago. I tried to talk to her about everything going on because the past 7 years, I have stayed quiet and not said anything because I didn’t want to get in her business, but now I have tried to speak my mind, and she just ignores me and won’t talk to me for days if I try to say something. I don’t know what to do. Should I talk to her mom? Should I stay out of it? I just don’t know. Its hard watching her do this to her child I feel so badly for him. But do I have a place to say anything? I just don’t think I can continue being friends with someone like this. Advice please?