27 parts Complete Hailey Upton-Halstead received a call while at work one day that she never thought she'd get. She had a little sister, barely 4 years old, abandoned at Chicago Med, beaten. Her mother had signed custody over to her and fled. Now she had a decision to make with her husband, Jay. Set starting towards the end of season 5; Hailey and Jay are married but no one in the unit (except Voight and Trudy) knows.