Washington: White House hopeful Hillary Clinton`s daughter Chelsea announced Monday she is pregnant with her second child.
"Next summer, Charlotte is going to be a big sister!" Chelsea Clinton posted on Twitter, adding that she felt "very blessed and grateful this holiday season."
The birth would come in the middle of the intense battle for the US presidency.
Chelsea`s mother is the Democratic frontrunner and is widely expected by next summer to be her party`s nominee, ahead of the November election.
Hillary Clinton routinely invokes her two-year-old grandchild on the campaign trail, assuring audiences that little Charlotte acts as a sources of pride and inspiration for her presidential ambitions and efforts to tear down barriers for young people and women.
"When I look at my new granddaughter, I think to myself, `We are going to do everything we can to make sure she has opportunities in life,`" Clinton said in a September campaign ad.
"You should not have to be the grandchild of a former president to know that you can make it in America," she said.
Chelsea Clinton, 35, is vice chair of the New York-based Clinton Foundation, which was launched in 2001 by her father, the former president Bill Clinton.