How long did it take for Jacob’s children to be born?

Answer:

Let's start out by putting boundaries on when the children were born. Jacob came to Haran and quickly fell in love with Rachel, the daughter of Laban. When offered a job by Laban, Jacob negotiated his wages. "Now Jacob loved Rachel; so he said, 'I will serve you seven years for Rachel your younger daughter'" (Genesis 29:18). Laban, however, reneged on the deal and tricked Jacob into marrying Rachel's sister Leah. He then offered Jacob another deal. He could marry Rachel in one week if he would continue working for him for another seven years (Genesis 29:27).

It would be during this time, then that Jacob began having children. At the end of his additional seven years, Jacob said he would be leaving. "Give me my wives and my children for whom I have served you, and let me go; for you know my service which I have done for you" (Genesis 30:26). This proves that the children were born during the years Jacob served for Rachel's hand.

But Laban convinced Jacob to stay on, this time for wages. "And Laban said to him, 'Please stay, if I have found favor in your eyes, for I have learned by experience that the LORD has blessed me for your sake.' Then he said, 'Name me your wages, and I will give it'" (Genesis 30:27-28). They settled on Laban giving Jacob the least desirable portions of his flock (the variegated colored sheep and goats). But Laban kept changing the terms of the wages, and finally, Jacob decided to leave after God said He would be with him. "Thus I have been in your house twenty years; I served you fourteen years for your two daughters, and six years for your flock, and you have changed my wages ten times" (Genesis 31:41).

Thus we see that most of Jacob's children were born during the thirteen-year timeframe that Jacob lived with Laban. The last son, Benjamin was born on the journey back to the southern part of Canaan (Genesis 35:18). However, it was several years later. Joseph was born just after Dinah's birth (Genesis 30:21, 24). She was of marriageable age in Genesis 34. Joseph was 17 in Genesis 37. Most scholars estimate that Benjamin was probably about fifteen years younger than Joseph.

Though the records in Genesis are basically in time order, it doesn't mean there isn't some overlap in successive stories. For example, the story of Judah's family in Genesis 38 probably overlaps with Joseph's years in slavery that starts in Genesis 39. But rather than switch back and forth between to the two overlapping stories, the two are told as a complete sequence, making it easier to follow. For the same reason, it is likely the story of births of Jacob's children (Genesis 29:31-30:24) likely overlaps with the story of Jacob's labors for Laban (Genesis 30:25-43) but are told as complete stories to make it easier to follow.

Another way to calculate this is to look at the minimums possible. At the absolute minimum, a woman can have a child once every 10 months -- though this is highly unlikely. Leah has 4 sons and then wasn't able to conceive for a while. Since it would have been several months to discover this fact, we could assume that at the minimum, four years passed by. Bilhah was then given to Jacob and they had two more sons. It is possible that these sons overlapped with Leah's. This means we need to add on at least one more year, or possibly two. It was only after Leah realized she had stopped bearing that she gave Zilpah to Jacob. Again, most likely Gad was born after Naphtali, but for argument's sake, we could say that Bilhah and Zilpah's children were intermixed. It was after these children that Leah had two more sons and a daughter. It is clear that Rachel did not conceive until after Dinah was born. This would give us a minimum of eight years, but more likely a minimum of ten years. The time span of thirteen years, as stated in the text, makes the most sense.