Is a questioner considered undutiful to his father who did not care for him or ask about him throughout his life, especially since his mother refuses his contact with him, and he holds no feelings for him whatsoever, knowing that he is dutiful to his mother and his kin? And is his mother sinful for not preferring this contact?

A father is accountable before Allah for the care and financial support of his children, and his neglect in this regard is a grave sin that exposes him to Allah's wrath. Nevertheless, a father still deserves dutifulness and obedience in what is right, even if he abuses or wrongs, due to Allah's saying: "And accompany them in the world with beneficence." Therefore, you must maintain ties with your father through visits, communication, care, and supplication, and beware of any ill-treatment towards him that falls under undutifulness. Your mother does not have the right to prevent you from maintaining ties with your father, and it is better to visit him without your mother's knowledge if that causes her sadness, so as to combine dutifulness to both parents. You are not to be blamed merely for not feeling love towards your father or for disliking his actions, because you have no control over these feelings.