Beast (2009)

Ten year old Benjamin and his mother live on an isolated farm under the violent reign of his father. Mother takes the beating and tries to cover up to keep things normal. But when Benjamin one day witnesses this beating, his suspicions are turned into facts. Benjamin wants his father to apologize to his mother for hitting her. Benjamin naively believes that things can be set straight with words alone. When Benjamin worsens the situation by taking his father's puppy as a hostage things escalate to a point where his mother has to step up and do what she should have done a long time ago.

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