The family relocated in order to care for Harry's mother Tabitha (Jessica Walter).Sachs found Milligan to be "really funny", and changed Ethan to better represent his personality.She and Ethan later part ways and she gets back in Naomi's good books.In the season finale after prom, Annie is framed when Naomi's sister Jen ends up in bed with Liam.In the morning Annie is seen driving with the now half empty bottle of vodka.
She falls in love with Jasper, a drug dealer and the nephew of the man she killed.
Mc Cord was cast because, according to Sachs, "she's someone who is worldly, and there's a sophistication to her that's interesting." Sachs and Judah had seen Grimes' work before and knew "she had the acting chops", and she was cast after acting a dramatic scene which she "just killed".
Sachs stated, "she can act, she's beautiful, and she can give this sweet cuteness [that lets us see] through her eyes into this world." Lori Loughlin auditioned for the role of Debbie and was given the part immediately.
She is based in part on Brenda Walsh from the original series.
She lives with her parents, Harry and Debbie, her adopted brother Dixon (whom she considers her best friend) and her grandmother Tabitha.