Constantly stuck between not wanting to let my 7 y/o sister in law do something she's not supposed…

Constantly stuck between not wanting to let my 7 y/o sister in law do something she's not supposed to & being like fuck it she's not my daughter 🙄 Her attitude & shit makes me wanna rip my hair out & seriously makes me not want her around my kid (which I know is dramatic, by the time my baby will be able to pick up on other's behaviors like that she'll probably have grown up some - I hope 😫)