According to a news release from her publicist Bob Merlis, Smith was under a physician's care when she died, reports The Hollywood Reporter.
She began singing with Louis Prima's band while she was still a teenager.
Smith and Prima married in 1953, and together, they won a Grammy in 1959 for their hit 'That Old Black Magic,' which stayed on the charts for 18 weeks.
She was also Grammy-nominated later in life for the 2001 album 'Keely Sings Sinatra.'
Smith established a notable solo career with her milestone recording of 'I Wish You Love' in 1957, produced by Nelson Riddle.