Robin Gibb
From Muppet Wiki
Robin Gibb and his children visit Oscar the Grouch
Robin Gibb (b. 1949) is a singer and songwriter who, with brothers Barry and Maurice, formed the group The Bee Gees, becoming an influential part of the disco era. Gibb personally helped usher Sesame Street into the world of glittering balls and Grover impersonating John Travolta, by serving as guest vocalist on the album Sesame Street Fever.
The Bee Gees song "Stayin' Alive" was later performed on The Muppet Show.
