Mull (1989)

A teenage girl has to terms with her family and herself when her mother falls critically ill. She decides to leave school to look after her family, which turns outto be an enormous challenge, as she has to deal with her father’s fanatical religion, her brother’s experimentation with drugs and homosexuality, her desire for the wrong boy, and her younger brother and sister’s inability to cope with the family’s instability.

Unfortunately the movie Mull is not yet available on HBO Max.