Help my sister.

So my mother is so controlling that she is starting to ruin my sister's life before it's begun. My sister has a job and goes to high school and soon college. My mom doesn't let my sister take the car anymore even though my mom doesn't work or anything. She tries her best to get rides, but really needs my mom's help and my mom makes her late to work and school every time she asks my mom to drive her. I am going to look into getting my sister her own car, but I need an insurance company that has low monthly payments for her and I to pay together. We live in Utah. Does anyone know of any companies we could look at? Please help. Thank you in advance.