Daniel's prayer [Daniel 9:16 Lord, in keeping with all your righteous acts, turn away your anger and your wrath from Jerusalem, your city, your holy hill. Our sins and the iniquities of our ancestors have made Jerusalem and your people an object of scorn to all those around us.]One of the curses for disobedience mentioned in old testament says :[Deuteronomy 28:18 The fruit of your womb will be cursed, and the crops of your land, and the calves of your herds and the lambs of your flocks. ] When David sinned against the Lord ( referring to his sin related to Bathsheba Uriah's wife) his son conceived by her was given death by God, his two sons died , one of his daughter got raped . There was a visible impact of his sin upon the lives of his children. I believe there are seeds of sin or weakness to act rightly that may be in our lives because our ancestors couldn't overcome some temptations in their lives. For instance Abraham called Sarah his sister when she was his wife, We find Isaac doing the same mistake, but when it comes to Jacob we find He labored freely 14 years for his two wife's. Jacob would never call his wife's sister He overcame that weakness. Or the Blessing he received helped him to purge away the ancestral weakness.