Having older kids

I have a 2 and 4 year old my 2year old don’t really give me the blues he going through the 2s but my 4 year old on the other hand don’t listen sneak snacks when told not to will only do her school work when she feels like it I’m tired of popping her and tbh tired of repeating myself her dad would even call me cause she talks back to him or just don’t listen I understand it might be normal but how do I keep cool with handling this I was never allowed to act this way and when I respond the way my parents did my mom will step in and say no it’s ok which makes me annoyed cause I don’t want her thinking it’s ok