"He was smiling and he knew we were all there," she said. "It's actually pretty awesome to live 100 years to the actual day. I think he would have been pleased."

According to a number of actuaries, the chances of living to be 100 years old to the day is rare, particularly for someone born in 1912, when life expectancy was considerably lower than it is today. Factor in the probability of being born on a leap day, 1 in 1,461, and Keller is unusual indeed.

“In the days before he died he kept asking my mom, 'How much longer until I'm 100? How much longer?'” said Katie Schoellhorn, 34, Keller's granddaughter. “And so she told him, you know, '3 days.' So that's how long he waited.”

After his death, family members and friends went ahead with the planned birthday party, which Schoellhorn described as a celebration of Keller's life. They put a sash that said “100 years old” on an empty chair, told stories and sang some of Keller's favorite songs. His grandchildren blew out the 100 candles on his birthday cake.

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