Phoebe Buffay

In the pilot episode, Phoebe is introduced as one of the six original friends, including neighbors Joey (Matt LeBlanc) and Chandler (Matthew Perry), former roommate Monica (Courteney Cox), Rachel Green (Jennifer Aniston), and Monica's brother, Ross (David Schwimmer). She is a musician at their typical meeting place, Central Perk, where she plays guitar and sings self-written songs. During the first season, she has a myriad of boyfriends, including Tony, a physicist named David, played by Hank Azaria, and a psychologist named Roger, played by Fisher Stevens. Phoebe's twin sister, Ursula Buffay, a character originally created for and appearing in the American sitcom Mad About You as a waitress, is also introduced in the first season, in ``The One With Two Parts''. Ursula is also portrayed by Kudrow. Phoebe works as a temporary secretary for Chandler for a brief period of time in ``The One With The Ick Factor''. It is revealed that the woman Phoebe believed was her mother, Lily Buffay, committed suicide when Phoebe was about 14, by means of carbon monoxide poisoning.

Question: does phoebe buffay really have a twin sister
Answer: no