GAIL: She’s going to be beautiful.
SUSAN: Yeah, you and Christopher are like a poster for Aryan breeding.
Susan refers to Lebensborn e.V. (meaning “Fount of Life” in German), an SS-initiated, state-supported, registered association in Nazi German with the stated goal of increasing the number of children born who met the Nazi standards of “racially pure” and “healthy” Aryans, based on Nazi eugenics.
The Aryan race is an obsolete historical race concept that emerged in the late-19th century to describe people of Proto-Indo-European heritage as a racial grouping. There is no evidence to support this. By the 1930s, this false concept was used to promote white supremacist ideology, portraying so-called “Aryans” as the “master race” – ideas which formed part of the ideology which led to the Holocaust.
Appallingly, Susan implies white “Aryan” babies are naturally beautiful (even before they are born!). To add to the discomfort, she says this in front of Gail, who is black. I think this is meant to tell us just how awful Sherry’s friends are, and by extension, Sherry herself.