Abraham and his wife Sarah are promised a son. It’s taking a long time so she has Abraham impregnate her handmaid, Hagar. Hagar has a son called Ishmael. But eventually Sarah has her own son, Isaac, and casts Hagar and Ishmael out into the wilderness.
Isaac, the favoured younger son, marries Rebekkah, and has two sons. He favours the older son, Essau. Rebekah favours the younger son, Jacob. She tricks Isaac into making Jacob his heir instead of his favourite son.
Jacob falls in love with a woman but is tricked into marrying her older sister first. He ends up marrying both of them and having 12 sons with 4 women (his wives and their handmaids) and he favours the youngest two because they’re the sons of the wife he loves. The older sons sell the second youngest into slavery because they’re mad dad favours him.
I guess the moral is parents shouldn’t play favourites
Jewish people bless their children to be “like Ephraim and Menashe.” They are two of the sons of Joseph and pretty minor characters in the story, but they are the first brothers who are treated without favoritism and actually get along.
It’s good Joseph finally broke the cycle