Step daughter out of control 😭

So I have a 5 year old step daughter. Me and my husband got custody in October of last year because her mother is in and out of jail. So my husband won. As of February of this year she’s been out of control and being disrespectful towards me. I’ve never seen a kid act out this way. She’s always been so sweet and now she tells us that we aren’t her family and her moms family is her family. She just told me that her mom can beat me up. I honestly don’t know what to do. She just got back Sunday from her moms and every time she comes back she’s worse. She only goes every other weekend. She brings up that her mom went to jail for punching a girl and it’s like its normal. What advice do you think you ladies can give me