Is a mother obligated to obey her husband if he forbids her from speaking to her son? And is a son obligated to give his father money, even if the father is late in repaying his debts?

A wife's obedience to her husband is confined to what is permissible. She is not obliged to obey him if he commands her to commit a sin. For instance, if your father forbids your mother from speaking to you, that is a command to sever ties of kinship, and he should not be obeyed in this matter, for the Prophet, peace and blessings be upon him, said: "There is no obedience to a created being in disobedience to the Creator." If your mother speaks to you, divorce occurs according to the majority of jurists. Regarding the money your father is asking for, if it is a debt, you must repay it. If it is assistance and he is in need, you must treat him kindly by providing what does not harm you or cause you undue hardship.