Out of all of Jacob's daughters, Rachel is "the pretty one." She's the daughter the boys swoon at and her sisters scoff at. She's the one Jacob plans to marry first, and her beauty is often the cause of some heavy jealousy among the other gals.
Here's how Dinah describes Rachel:
Rachel's beauty was rare and arresting. Her brown hair shaded to bronze, and her skin was golden, honeyed, perfect. In that amber setting, her eyes were surprisingly dark, not merely dark brown but black as polished obsidian the depth of a well. (1.1.12)
Hmm, "golden, honeyed, perfect"? Now that's a description for ya. You'd think Rachel would be a Victoria's Secret model from the way that Dinah talks about her. So it's no surprise that Rachel's rare beauty goes to her head when she's a child. She certainly thinks she deserves the best—and that means she deserves better than her sisters. For example, after Leah marries Jacob (as a favor for Rachel, we should add), Rachel explodes:
"You evil-eyed lummox, you only wish Jacob loved you as he loves me, but he never will. I am the one. I am his heart. You are a brood mare. You pathetic cow." (1.2.59)
Ah, typical sisterly love. Rachel's quite the firecracker when she's younger. When it comes down to it, she's beautiful, but short-tempered and often downright nasty.
Rachel's beauty, however, doesn't translate into childbearing ability. Rachel has countless miscarriages, and when even Bilhah gives birth to a child at Rachel's knees, Rachel becomes even more distressed about not being a mother. So Rachel becomes a midwife—and that defines her adult character. As Dinah says, "Years attending so many births made Rachel's heart tender" (1.3.21).
But Rachel's tender heart is also a vulnerable heart. She grows increasingly more depressed about not having given birth to a healthy child, and she eventually whispers to the gods, "Give me children or I will die" (1.3.24).
Rachel's almost a tragic character for most of the book: she's beautiful, but she's tricked into not marrying Jacob. She can't give birth to any children, so she becomes a midwife—which doesn't seem like a great profession for someone who feels disappointed about not having given birth. It's like a constant reminder of what Rachel doesn't have.
Fortunately, Rachel becomes one of the best midwifes in the land, and she does end up giving birth to two children.
… But the second child kills her. You can't have it all, we guess.