She makes her return to Wisteria Lane in Season 6, when her mother intentionally stabs herself. Susan realizes that Katherine needs serious mental help, and upon learning that only a family member can commit someone to a mental institution, she calls Dylan, pretending to be a doctor, and tells her she should come to Fairview. At first, Dylan not only believes Susan attacked her mother, but also thinks Katherine is married to Mike; however, after Susan shows Dylan her wedding album, Dylan realizes that her mother has been lying to her and living in delusion. When Dylan visits Katherine, she confronts her mother. Katherine goes into a full blown meltdown and both Susan and Dylan watch as she is restrained.