Proverbs 15:20

This is like Proverbs 10:1, but the second line is different. ‘A foolish son causes pain to his mother.’ (Proverbs 10:1). ‘A foolish son hates his mother.’ (Proverbs 15:20)

The foolish (or evil) son might not think that he hates his mother. However, his evil actions prove that he hates her. He causes trouble and pain for her, because he does evil things.