Phoebe's twin sister in the TV show Friends is called Ursula Buffay. Ursula, portrayed by Lisa Kudrow, is a recurring character throughout the series. She is depicted as Phoebe's polar opposite, often portrayed as selfish and lacking empathy. Ursula initially appeared in the sitcom "Mad About You," also played by Lisa Kudrow, before making crossover appearances as Phoebe's twin sister in Friends.