The new FX comedy, based on an Australian series, stars Elijah Wood as Ryan.
Ryan meets a man called Wilfred (Jason Gann). The rest of the world sees Wilfred as a dog, but Ryan believes that he is talking to a man dressed in a dog suit.
According to Deadline, Brown has now joined the cast as Ryan's older sister. The character, who is described as a "controlling" and "condescending" obstetrician, was reportedly played by Andrea Savage in the pilot.
Brown played Katie in Roommates and has had guest roles in shows including Romantically Challenged, Accidentally On Purpose, Psych, Cold Case and Mercy.