She was the “most beautiful woman in Puppetland” in the 1980s children’s show starring Paul Reubens, and more recently had a recurring role in “It’s Always Sunny in Philadelphia.”

Lynne Marie Stewart, known for her work in 'Pee-wee's Playhouse' and 'It's Always Sunny in Philadelphia' has died at age 78.

Stewart had a memorable role on the beloved comedy series “It’s Always Sunny in Philadelphia,” playing Charlie Kelly’s mother, Bonnie.

The sad news was announced Friday by Stewart’s longtime friend, actress Cassandra “Elvira” Peterson, in a tribute shared to Instagram.