Chihuahua biting baby

So I live with my mom and fiancé and daughter. My daughter just turned 1 and has already been bitten by my moms dog 3 times. Each time, the dog just ran up to her out of nowhere and nipped her for no reason. She is a very aggressive dog, she barks at everyone that doesn’t live here, she runs out the house and attacks neighbors and other big dogs. I told my mom to give her to someone else or to take her to the shelter because she is just too aggressive but she won’t. I don’t know what to do. She’s way to mean to be anywhere near my daughter or anyone! She’s bites our guests and other family members. Should I just take her to the shelter behind my moms back?