LOS ANGELES — Valerie Harper, who scored guffaws, stole hearts and busted TV taboos as the brash, self-deprecating Rhoda Morgenstern on back-to-back hit sitcoms in the 1970s, has died.

Longtime family friend Dan Watt confirmed Harper died Friday, adding the family wasn’t immediately releasing any further details. She had been battling cancer for years, and her husband said recently he had been advised to put her in hospice care.

Harper was a breakout star on “The Mary Tyler Moore Show,” then the lead of her own series, “Rhoda.” She was 80.

She won three consecutive Emmys (1971-73) as supporting actress on “The Mary Tyler Moore Show” and another for outstanding lead actress for “Rhoda,” which ran from 1974-78. Beyond awards, she was immortalized — and typecast — for playing one of television’s most beloved characters, a best friend the equal of Ethel Mertz and Ed Norton in TV’s sidekick pantheon.