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Veteran entertainer Andy Williams has died at the age of 84 after a year-long battle with bladder cancer.

Williams, whose signature tune was "Moon River," passed away at his home in Branson, Missouri Tuesday night, his representative confirmed in a statement released Wednesday morning.

Williams' last posting on Twitter was September 22 at just after 11:00 pm, a single word: "Sigh."

Williams was a performer from childhood, singing with his brothers from the age of 8 as part of the radio act the Williams Brothers Quartet. In 1951, the act disbanded and Williams moved to New York, where the handsome 24-year-old became a regular performer on Steve Allen's "The Tonight Show."

Those appearances landed Williams a recording contract and began a career that earned him five Grammy nominations, 10 gold and three platinum albums, most of which came during his 25-year association with Capitol Records.

However, Williams' biggest hit was the Oscar-winning "Moon River" from "Breakfast at Tiffany's," which ultimately became the song most associated with him.

Easy-going and photogenic, Williams also was a television regular in his heyday, appearing on the top variety shows and hosting several of his own, including the Emmy-winning "The Andy Williams Show," which debuted on NBC in 1962 and aired for nine years. His Christmas specials were holiday family-viewing staples.

With his broad popularity waning, Williams moved to Branson in the early 1990s and opened his own Moon River Theatre there, where he performed regularly until his bladder cancer diagnosis ended his appearances. He released his best-selling autobiography, titled "Moon River and Me," in 2009.

Williams was married twice. In lieu of flowers, Williams' family asks that donations be made to the Bladder Cancer Advocacy Network.