On Sunday, the family released a statement:
"It is with the deepest sadness that we announce the sudden passing of our beloved husband, father and friend, Frank Gifford. Frank died suddenly this beautiful Sunday morning of natural causes at his Connecticut home.
"We rejoice in the extraordinary life he was privileged to live, and we feel grateful and blessed to have been loved by such an amazing human being," the statement continued. " We ask that our privacy be respected at this difficult time and we thank you for your prayers."
Gifford is survived by Kathie Lee Gifford, currently the fourth-hour co-host of NBC’s Today, and their two children, Cody, 25 and Cassidy, 22, as well as three children, Jeff, Kyle and Victoria, from a previous marriage.
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After announcing his death, Kathie Lee Tweeted a thank you to fans for their outpouring of support.
Deeply grateful to all 4 ur outpouring of grace. We r steadfast in our faith & finding comfort in knowing where Frank is. Phillippians 4:13.— Kathie Lee Gifford (@KathieLGifford) August 9, 2015
Kathie Lee's friend and cohost, Hoda Kotb, Tweeted a photo of a carefree moment in his memory.
"This is how I will remember #frankgifford -- always making us laugh," she wrote on Sunday. "But today I am heartbroken -- love u klg."
Even those not overly familiar with Gifford's extraordinary record in pro football– which included a championship season for the Giants in 1956, a famous comeback in 1962 nearly two years after an on-field injury, membership in the Hall of Fame – knew Frank from his marriage to Kathie Lee.
Some thought the couple were in danger of capsizing in 1997, when a tabloid paid a woman to invite Frank up to a hotel room. Kathie Lee faced down with the scandal with even-handed dignity, and the crisis finally passed.
Despite occasional forays into movies and TV performances – he was usually cast as himself, notably in Jerry Maguire – Gifford's natural home proved to be as an on-air sports commentator: Monday Night Football and Wide World of Sports.
"Week after week he made one after another catch more incredible than its predecessor … Oh, how I laughed and jumped up and down, exclaiming, 'Oh, good, Frank! Good! Very good indeed!...' One had to hand it to the guy, his gift for living out his dreams."