Bill and Hillary Rodham Clinton are grandparents.
Their daughter, Chelsea, gave birth Friday to her first child, Charlotte.
Chelsea Clinton announced the news on Twitter and Facebook early Saturday, saying she and husband Marc Mezvinsky are "full of love, awe and gratitude as we celebrate the birth of our daughter, Charlotte Clinton Mezvinsky."
Clinton spokesman Kamyl Bazbaz said the child was born Friday but did not immediately provide additional details. The couple lives in New York City.
The former president and former secretary of state quickly retweeted their daughter's message on Twitter but did not immediately comment on the baby's arrival.
The news comes as Hillary Clinton deliberates whether to run for the White House in 2016. She is the leading Democratic contender to succeed President Barack Obama, her 2008 campaign rival, and has said she expects to make a decision around the beginning of next year.
The baby has been eagerly anticipated as Hillary Clinton considers her political future. She has called the prospect of becoming a grandmother her "most exciting title yet." She even has picked out the first book she intends to read to her grandchild, the classic "Goodnight Moon."
She has said she didn't want to make any decisions about another campaign until the baby's arrival, pointing to her interest in enjoying becoming a grandmother for the first time.
Bill Clinton, who canceled a fundraising visit Saturday to Denver for Democrats running for the Senate and governor, has been eager to become a grandfather.
During an event with former President George W. Bush in September, Bill Clinton's cellphone rang on stage and he joked that only two people had the number "and they are related to me," musing that he hoped he wasn't becoming "a premature grandfather."
"Every day I get up and I say, 'You have to remember whose child this is. Do not interfere. Be there when you are welcome. Be loving but not judgmental," Clinton said to laughs in an interview with CNN at his annual Clinton Global Initiative, only days before the baby's arrival.
The 34-year-old Chelsea Clinton said in an interview with Glamour magazine last year that she and her husband had hoped to make 2014 "the year of the baby." She announced her pregnancy in April at the end of a forum in New York on female empowerment.
"I just hope I will be as good a mom to my child and, hopefully, children as my mom was to me," she said at the time.
Chelsea Clinton grew up in the public eye as a teenager in the White House, later graduating from Stanford and Columbia universities. She worked in finance in New York and in public health, earning a doctorate from Oxford University.
She serves as vice chair of her family's foundation, which was renamed the Bill, Hillary & Chelsea Clinton Foundation, and helps direct the organization's humanitarian and philanthropic efforts around the globe. She recently departed NBC News, where she served as a special correspondent.
The new parents, who married in 2010, were friends as teenagers in Washington and both attended Stanford. Mezvinsky is a hedge fund manager and the son of former Reps. Majorie Margolies of Pennsylvania and Edward Mezvinsky of Iowa, longtime friends of the Clintons.