Lisa is the aunt of Ross Geller and Monica Geller. She was portrayed by Ellen Gerstein in "The One In Massapequa".
History
Lisa and her husband Dan are at Jack and Judy's anniversary party and they see Ross and Rachel and congratulate them on their baby and their "wedding". She was last seen listening to Ross and Rachel's made-up stories about their made-up wedding, due to the fact Ross’ parents had lied to Lisa and some others about Ross and Rachel’s relationship and that they married.