Dr. Spencer played the wisecracking Dee Thomas on the 1970s sitcom “What’s Happening!!” and became a veterinarian later in life.

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.

Child star Danielle Spencer, who portrayed Dee Thomas on the 1970s comedy TV series “What’s Happening!!,” has died at 60, according to former co-star and friend Haywood Nelson.