Poor Substitutes

After a woman mistakes Sarah for someone else's daughter, she decides to try to find her birth mother. They find her on the list and Bailey calls her behind Sarah's back. He meets her. She's an actress and she tells him that she doesn't want to meet her. Bailey tells Sarah that the woman in the list is not her mother, killing her hopes. Charlie tries to teach Owen how to poop in the potter so he can go to pre-school. Claudia is shocked when she finds out that Kristen is dating a guy. She tries to make Kristen come back to the family, but Kristen tells her that she has to move on. Justin's friend Allison comes from England to visit him. At first, Julia is jealous, but then they really get along. Allison comes on to Julia, who later reveals her secret. Julia advises Allison not to run away from her problems.