Abraham lived a long and full life. The phrase “he was gathered to his people” is saying that his family all gathered together before he died. Isaac is an often overlooked patriarch and that is not justifiable. Isaac was the only one who stayed in the land. He is the only one who was monogamous. He was also the only one who did not have his name changed. His life also displayed great faithfulness and trust in Elohim.
Elohim visited Sarah and made her fertile. A full 25 years had passed since Elohim first promised prosperity to Abraham. It was a year after Elohim last visited Abraham and Sarah and she bore a son just as promised. This is the first recorded instance of circumcision on the eighth day.
Hagar was an Egyptian and was probably given to them by Pharaoh when they went to Egypt and Sarai was taken to Pharaoh. Hagar was given to Abram as a wife as desired by Sarai. We should keep in mind that all wives are not equal. If a man had more than one wife, one wife was primary and the others had a lower status. In this case, Sarai had primary status and Hagar was a lesser wife subject to Sarai as well as Abram.