I have a 5 year old daughter, very well behaved. My bf has a son(4), and a bratty 6 year old daughter that acts like she's 3. I an pregnant with his child, only 9 weeks. I can no longer take the crap from his daughter. She yells at him, screams when she doesn't get her way, throwing these temper tantrums, squeezing her fists together and giving a look of pure hatred I've never seen on a child. I have tried to blow it off, unfortunately my daughter has started to copy this behavior. I don't know how much longer I can take this. They are at my house every single day!