Andrea Barr is the widowed mother of Lucas Barr and the daughter of Sheriff Jake Devins. The vengeful spirit of Peter Sweeney drowned Andrea's husband in Lake Manitoc before coming after both her and her son. Sam saves her when she almost drowns in the bathtub, and Dean saves her son from drowning in the lake.
Sam and Dean first meet her in the police station when she is dropping off her son, Lucas. Dean asks her to show them to a nearby motel and she agrees. Once there she lets them know that Dean's flirting won't work on her and walks away. They see her again when she is with her son in the park. Shes tells Sam that Dean's "Jerry Maguire" act won't work. She is surprised when Lucas responds to Dean. Later on, Sam and Dean come by her house to talk to Lucas and she takes them to his room. There she watches in amazement as Dean gets through to Lucas. After her father chased them out of town, the spirit in the water, Peter Sweeney, attempts to drown her in her tub, but Sam saves her. After the almost drowning, she is pretty spooked and thinks shes going crazy. She also gives Sam and Dean crucial information that leads them to finding the last clue to why these drownings are happening. Then her father shows up and pulls a gun on Sam and Dean. She tries to talk her father to put the gun down, but notices Lucas is gone. Lucas falls into the water, and Andrea tries to go after him but cannot because the spirit wanted them both. Her father sacrifices himself for Lucas. Lucas is then released and Dean pulls him up to the surface of the water. As Sam and Dean are leaving, Andrea and Lucas bring them sandwiches. She kisses Dean and thanks them both.