Brianna is first seen in season 3 episode 8, "All In." She was in a car accident with her foster mother. It was revealed that she has cystic fibrosis. She was going to be adopted by her foster mother, but that did not happen due to her foster mother's death. She was in the hospital while her mother was being worked on. Drew and Shannon made her feel at home, and she slowly took a liking to Drew. Soon after, Drew and his husband Rick decide to adopt her. During the adoption process, her biological father shows up, claiming to have been looking for her. Unfortunately, he has the legal right to custody of her, per the law, despite Brianna wanting to live with Rick and Drew as her two dads. During the episode, Drew is very guarded and quickly figures out her biological dad is only there to try to bribe them for money. Once that's found out, the biological father leaves after Rick threatens to arrest him for extortion.
As of season 3 episode 13, Brianna is living with Drew and Rick. She appears briefly in episodes of season 4; most notably in season 4 episode 5 where she meets her grandmother, Drew's mom, at the end of the episode.