Danielle Spencer, who played the wisecracking little sister Dee Thomas on the 1970s sitcom “What's Happening!!” has died. She was 60.

Former child star Danielle Spencer, who brought sass as little sis Dee in the 1970s sitcom 'What's Happening!!,' died Monday after battling cancer. She was 60.

Danielle Spencer — the beloved actress who played “Dee” on the classic sitcom What’s Happening!! — has passed away at age 59, and her family is opening up about the devastating chain of health struggles that led to her death.