Charles Ellicott Commentary Genesis 29:18

"And Jacob loved Rachel. And he said, I will serve thee seven years for Rachel thy younger daughter." — Genesis 29:18 (ASV)

I will serve you seven years for Rachel your younger daughter. —Hebrew, your daughter, the little one, just as Leah, in Genesis 29:16, is called the great one. (See Note on Genesis 9:24.) So in Genesis 44:20, the phrase “the little one” simply means the youngest.

Wives had to be purchased in the East (Genesis 24:53), and as Jacob had brought no rich presents, such as Abraham had sent when seeking a wife for his son, he had only his personal services to offer. As the sale was usually veiled in true Eastern fashion under the specious form of freewill gifts, we shall find that both Leah and Rachel are offended at being thus openly bartered by Laban.