Child Protective Service, Should I call?

Backstory: I have known this woman for over ten years, she has an alcohol problem with history of violence while drinking. We had a falling out because of her problems and just now started to get back in touch, thinking she had got help for herself specially after having a child. Her son is overly aggressive and has been for months towards adults and children a like.
Issue: I called last night to confirm some plans to get together and catch up but while we were on the phone she said "hold on a second" and in the backround I heard her scream at her 1 year old "g*d d*mn it you a*shole, what the f*ck were you thinking? f*cking little a*shole" (she used the childs name but for obvious reasons Im keeping this as anonymous as possible)
After returning to the phone I was mortified, she then began to joke about calling her one year old an a*shole and was not ashamed to almost brag about it. Note that it was because he was stepping on some paper. Now Im a parent myself, Im dedicated but not perfect. So I mentioned it being a extreme and she told me, "he is horrible he is an a*shole" and then suggested he come stay with me awhile so he would learn to be a nice boy.
Should I call someone? Should it be investigated? There have been times I know they cant keep food in the house as well. I have talked to her but she doesnt seem to take what is going around her seriously. When I do she suggests I take him and let my son teach him to be a good boy instead of putting in the effort herself. I have only been around the little boy once without her there, and have not noticed any bruises or signs of physical abuse. But the signs for mental abuse are overwhelming.