Born on August 29, 1926, in Kansas City, Missouri, Lynn studied dance as a child, and by age 14 was performing in supper clubs and on the radio. She toured with the USO during WWII, including entertaining in active-combat zones. It is thought she was the only woman who traveled the treacherous Burma Road during the war.
After the war, she won a contract with 20th Century Fox, appearing in the films "Sitting Pretty" and "Apartment for Peggy" (both 1948) before starring in "June Bride" (1948) in the title role.
She continued acting in films, including "Cheaper by the Dozen" (1950), and went on to appear on TV's "The Egg and I" (1952), one of the medium's earliest sitcoms. She also starred on the sitcom "Where's Raymond?" (1953-1954), and quickly became a familiar face via TV guest spots.
Toward the end of her run on the serialized "Texas John Slaughter" as part of "The Magical World of Disney" in 1961, she was cast as Thelma Lou opposite Don Knotts as Barney Fife on "The Andy Griffith Show."
“I had seen the Griffith show twice before I went to read for the part,” Betty once said. “I remember that I laughed out loud — it was so funny. I didn’t do that very often. I thought, 'Gee, this is really unusual.'”
She appeared on 26 episodes of the series between 1961 and 1966. The only surviving cast member to have made more appearances is Ron Howard as Opie. Howard remembered her on Twitter Sunday, writing, "RIP Betty Lynn. She... brightened every scene she was in & every shooting day she was on set. I saw her last a few years ago where she still lit up the room with her positivity. It was great to have known and worked with her. She truly was 95yrs young."
In the TV movie "Return to Mayberry" (1986), Barney and Thelma Lou finally got married. It was a ratings hit.
After her initial run on "Andy Griffith" ended, Lynn played secretaries on the popular series "Family Affair" (1966-1968), "My Three Sons" (1967-1971), and "Matlock" (1986), reuniting with Griffith for the latter.
Along with other sporadic TV appearances, Lynn gave her final performance on a 1990 episode of "Shades of L.A.," after which she became a regular at "Andy Griffith" nostalgia shows.
She had reportedly just finished work on her autobiography, expected to be published in the near future.