Jess has a Sister!
Who’s that girl? It’s Jess’ sister!
Cardellini will take on the recurring role of Abby, Jess’ wild-child sibling, and will begin filming on the hit Fox sitcom this week. The actress, who is also known for her work on Freaks and Geeks and ER in addition to her Emmy-nominated turn as Don’s (Jon Hamm) neighbor-turned-mistress on Mad Men, will first appear in February.