Chelsea Clinton is Pregnant With Her Second Child, Bill and Hillary Are Over the Moon

Chelsea Clinton took to Twitter Monday to announce she is pregnant with her second child.

"Next summer, Charlotte is going to be a big sister! Feeling very blessed & grateful this holiday season," she wrote on social media, underneath a photo of 15-month-old Charlotte perusing a children's book titled "Big Sisters are the Best."

Read: Chelsea Clinton Pregnant With First Child

 Next summer, Charlotte is going to be a big sister! Feeling very blessed & grateful this holiday season. pic.twitter.com/gpCGqcmeCq

It didn't take long for Bill and Hillary Clinton to start crowing like proud grandparents.

"Your dad and I could not be happier for you, Marc and Charlotte. We're so excited to meet our second grandchild!" tweeted the favored Democratic candidate for the 2016 presidential election.

 Chelsea and husband Marc Mezvinsky, who were married in 2010, had their first child in 2014, with reporters and photographers camped outside New York City's Lenox Hill Hospital. 

Read: Chelsea Clinton Wedding Secrets Revealed

Former president Bill Clinton exclaimed online Monday  "Christmas comes early! Hillary Clinton and I are thrilled for Chelsea, Marc and Charlotte's growing family in 2016!"

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