Issac had two sons. Esau & Jacob. One was much worthier then the other. If Issac had them around age 60, then Abraham was about 160. Since we are told that he lived till 175, my question is why didn’t Abraham advise his son, Issac, to which one was the better to carry on the Jewish Heritage. Why did he have to be fooled by Jacob? Abraham must of known and have been able to give him advise. Nothing is ever mentioned about Abraham again till his sons bury him
Actually, our Medrash tells us that as a boy Esau was not too bad, and his behavior worsened after Avraham died. This was a special gift to Avraham who was promised that he will die satisfied.