When Joseph, Rachel’s first son, was born, Rachel requested that God grant her an additional son. The Sages relate that God received her prayer, but it was at the expense of the other matriarchs.

The initial formation of the child that was to become Dina, Jacob’s daughter from Leah, was male. After Rachel’s prayer, when she said: “May the Lord add another son for me” (Genesis 30:24), that child became female. All the matriarchs were prophets, and Rachel was one of the matriarchs. In recounting Rachel’s prayer, it is not written in the verse: May the Lord add more sons; rather: “Another son.” She said: Jacob is destined to produce one more son. I wish it will be from me. Rabbi Hanina said: The other mothers of Jacob’s children, i.e., Leah, Bilha, and Zilpa] convened and said: We have enough males, let Rachel be remembered by God and conceive another child. (Bereshit Rabba [Theodor-Albeck] 72)