What is the ruling on marrying a widow with children, despite the family's disapproval due to the perceived burden of additional responsibilities, especially considering the Hadith "Paradise lies under the feet of mothers" and the son's feeling of guilt towards his parents?

Your marriage to a woman with children and problems is commendable, and you will be rewarded for it, especially if she is religious, which is what the Prophet, peace and blessings be upon him, did. Your family's rejection of this is not binding. You must repent and seek forgiveness for your harshness towards your parents and try to please them. The hadith "Paradise is under the feet of mothers" is not authentic with this wording. It is superseded by the hadith: "Stay with her, for Paradise is under her feet."