From Muppet Wiki

The Pointer Sisters is a famous R&B group. The group's members originally included Ruth, Anita, Bonnie and June Pointer. The group found its greatest success as a trio after their sister Bonnie left to pursue a solo career. Its hits included "Automatic," "Jump (For My Love)," and "I'm So Excited."

The Pointer Sisters recorded the vocal tracks for the popular Pinball Number Count cartoon on Sesame Street.

Their song "Yes, We Can Can" appeared on the 1979 album The Stars Come Out on Sesame Street. They also sang "Hush, Little Baby" at one point.(YouTube)

They are parodied with a trio of singing pigs called The Oinker Sisters.

In 1982, they appeared with Jim Henson at the Night of 100 Stars.