The movie is 'unfit for' children. [=children should not watch the movie]
an 'unfit' parent [=a person who cannot care for a child properly]
Her sisters are overweight and 'unfit'. [='out of shape']
(..) She has merely broken a rigid and time-honoured... code of our society. A code so severe that whoever breaks it is hounded from our midst... as unfit to live with. She must destroy the evidence... of her offence. But what was the evidence of her offence? Tom Robinson, a human being. (..)1962 To Kill a Mockingbird