Burch, who was injured in a fall, died Sunday at a hospital in Santa Barbara, Calif., her family announced. Born Jan. 20, 1920, in Ephraim, Utah, she was the sixth of eight children of William King Driggs, a vocal trainer, and his wife, Pearl. Her father was an old-time vaudevillian who trained his children to sing. Billed as the Driggs Family of Entertainers, they toured the West, eventually settling in Oakland, Calif. When her three oldest sisters -- Maxine, Luise and Alyce -- formed their own vocal group in junior high, they billed themselves as the King Sisters. The trio became a quartet when Yvonne, then 14, joined with another sister, Donna, after Maxine left to get married. With another sister and a friend in the lineup, they became known as the Six King Sisters. They first attracted attention in 1935 by performing with Horace Heidt's band and appearing on his radio show. Heidt shrank the group to four when he took them on tour. Once again, they were truly a sister singing act, known for tight, four-part harmony, with Yvonne or Alyce taking the occasional solo. When guitarist Alvino Rey -- who by then had married Luise -- left Heidt in 1939 to form his own band, the sisters went with him. Yvonne sang on several Rey hits, including the band's theme song, 'Nighty Night,' and 'I Said No.' The King Sisters also scored a series of moderate hits issued under their own name, among them 'The Hut Sut Song,' 'I'll Get By' and 'In the Mood.' At the height of their musical success, they appeared in several movies in the 1940s, including 'Sing Your Worries Away' with Buddy Ebsen, 'Meet the People' with Lucille Ball and Dick Powell, and 'Cuban Pete' with Desi Arnaz. Upon entering the Navy, Rey broke up his band in 1943 and the sisters started fading from the spotlight. When Donna left the group in the late 1940s, the youngest sister, Marilyn, stepped in. In 1963, Yvonne organized a charity performance that featured members of the King family and led to their own weekly ABC program, 'The King Family Show,' in 1965. The program was an immediate hit, according to the All Music Internet database, but success was bittersweet: Family patriarch Driggs, a featured performer, died weeks into the show's run. With as many as 40 family members involved -- Rey had a regular spot with his talking guitar -- the wholesome program aired for a year. It was briefly revived in 1969. The King Sisters continued to perform into the 1980s and sang at Ronald Reagan's presidential inaugural gala in 1985. With her first husband, musician Buddy Cole, Yvonne had two daughters, Tina Cole, who played the wife of the character played by Don Grady in the TV show 'My Three Sons'; and Cathy Green. Twice divorced, Yvonne also had been married to bandleader Del Courtney. In 1966, she married William Burch, an early TV writer-director-producer. He died in 2005 at 86. In addition to her daughters, Burch is survived by sister Marilyn; stepchildren Cilla Reid and Charles Burch; six grandchildren; and three great-grandchildren. 