What was probability for Jacob (Israel) to have TWELVE sons and ONE daughter?

Jacob, later called Israel, was the second-born son of Isaac and Rebecca, the younger twin brother of Esau, and the grandson of Abraham and Sarah. According to biblical texts, he was chosen by God to be the patriarch of the Israelite nation. From what is known of Jacob, he had two wives, sisters Leah and Rachel, and two concubines, Bilhah and Zilpah, by whom he had thirteen children. The twelve sons form the basis for the twelve tribes of Israel, listed in the order from oldest to youngest: Reuben, Simeon, Levi, Judah, Dan, Naphtali, Gad, Asher, Issachar, Zebulun, Joseph, and Benjamin. Jacob was known to display favoritism among his children, particularly for Joseph and Benjamin, the sons of his favorite wife, Rachel, and so the tribes themselves were not treated equally in a divine sense. Joseph, despite being the second-youngest son, received double the inheritance of his brothers, treated as if he were the firstborn son instead of Reuben, and so his tribe was later split into two tribes, named after his sons, Ephraim and Manasseh.