143:18 One is not permitted to hit his grown son. “Grown” does not refer to his age but to his development. If one thinks that his son will oppose him with words or actions, even if he is not yet bar mitzvah, it is forbidden to hit him. Instead, he must only chastise his son using words. Anyone who hits a grown son will be judged for violating the commandment against putting a stumbling block in front of a blind person (i.e., misleading a person into doing the wrong thing – Leviticus 19:14).
143:19 A person must honor his step-mother, even though she is not his mother, so long as his father is alive. Similarly, one must honor his step-father so long as his mother is alive. It is appropriate to honor them also after his father or mother passes away.