(Reuters) -- Former U.S. President Jimmy Carter's 28-year-old grandson, Jeremy, has died, Carter told a church gathering on Sunday, the Atlanta Journal-Constitution reported.
The newspaper said Carter, who two weeks ago said he is now cancer-free, appeared at the Maranatha Baptist Church to teach his regular Sunday school class and told church members that his grandson had died a few hours before.
The cause of death was unclear. The 91-year-old former president told the church Jeremy Carter had felt unwell on Saturday and that his mother discovered his heart had stopped after he went to take a nap at his family's home in Peachtree City, Georgia, the newspaper reported.
Click through images from Jimmy Carter's 90th birthday:
Officials with the Carter Center, a nonprofit founded by the former president to promote peace and health, did not immediately respond to a request for comment.
Carter announced at the same church two weeks ago that he was cancer-free, four months after he revealed that his melanoma had spread from his liver to his brain. He continues to undergo regular treatment.
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"Life's full of its ups and downs and the Carters aren't immune," the newspaper quoted her as saying.
Carter, a former peanut farmer, served as U.S. president from 1977 to 1981, losing his reelection bid to Ronald Reagan. While his presidency has been derided by critics as unsuccessful, Carter has built a powerful post-White House legacy, winning a Nobel Peace Prize in 2002 and staying active into his 90s working for causes such as fighting disease in Africa.
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