Former President George H.W. Bush celebrated a record-setting birthday Tuesday, becoming the first U.S. president to reach 94 years of age.

The 41st president was at his family home in Kennebunkport, Maine, Tuesday -- and was also honored at the George H.W. Bush Presidential Library and Museum in Houston.

The museum said Bush's birthday is also a tribute to former first lady Barbara Bush, who died at the age of 92 in April.

Bush family spokesman Jim McGrath said called the birthday a "very low-key day with family."

No other U.S. president has reached 94. Ronald Reagan and Gerald Ford died at 93.

Former President Jimmy Carter will reach the milestone in October. Other living former presidents are Bill Clinton, George W. Bush and Donald Trump, all 71, and 56-year-old Barack Obama.

Son Neil Bush marked the event in a USA TODAY column that encourages Americans to volunteer.

"Dad also understood that government alone cannot solve all of our community challenges and, from his first day as president, he actively supported volunteer-powered service initiatives," he wrote.

"To celebrate my father's birthday, I want to recognize the 62.6 million Americans who volunteer every year and ask the next generation -- and the generation who raised them -- to take a moment to pledge your service."

Bush has been hospitalized twice since Barbara Bush's death and several times in recent years.

This article has been adapted from its original source.