The New Adventures of Old Christine (2006)

S1E1 Pilot

Christine's son, Ritchie, is thrilled to start at an upscale private school, but she quickly finds herself face-to-face with the pretentious class moms, Marly and Lindsay, who can't comprehend that Christine has a job. Living with her is her lazy brother, Matthew, who doubles as Ritchie's babysitter when needed. On Ritchie's first day, Christine is shocked to learn that her ex-husband, Richard, with whom she shares a surprisingly good relationship, is now dating a charming younger woman who also happens to be named Christine—the "new" Christine.