At the end of Parshat Toldot, Breisheet 28:5 we read: “And Yitzchak sent away Yaakov: and he went to Padan Aram to Lavan, son of Betuel the Aramian, the brother of Rivka, mother of Yaakov and Esav”.

Why does the Torah which does not waste words have to mention that Rivka was the mother of Yaakov and Esav? The entire Parsha talks about Rivka from her pregnancy with the twins, their childhood, their personalities and their fight for Yitzchak to bless them.

Rashi has so much difficulty with this pasuk that he actually says “I don’t know what this is here to teach us”.

The Riyva, Yehuda Ben Eliezer, a commentary on Rashi, suggests that the Torah wished to explain how it was that Yitzchak and Rivka came to have Esav, a wicked son. The text therefore mentioned that Rivka had some unsavory kinsmen.

Chizkuni points out that in the Gemara in Baba Batra110a it says that most children turn out to be similar to their mother’s brother. A woman’s brother is the male product of the upbringing that she received from her parents and therefore she is most likely to pass on some of those values to her own children. Chizkuni concludes that it is not unusual for Esav to be similar to Lavan.

The Gemara continues saying that one who seeks to marry a woman should first examine the character of her brothers.