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Chelsea Clinton tweets that she's pregnant with second child

Hillary Clinton will have the birth of her second grandchild to look forward to next year -- perhaps right around the time of her party's nominating convention.

Former U.S. Secretary of State Hillary Clinton and her daughter Chelsea Clinton listen as U.S. President Barack Obama speaks at the Clinton Global Initiative in New York, Sep. 23, 2014. 

Dec. 21, 2015, 8:58 PM UTC / Updated Dec. 21, 2015, 9:16 PM UTC

By Carrie Dann, Carrie Dann

Hillary Clinton will have the birth of her second grandchild to look forward to next year -- perhaps right around the time of her party's nominating convention.

Chelsea Clinton tweeted Monday that she's expecting a second child "next summer."

The Democratic front-runner frequently discusses her granddaughter Charlotte, who was born in 2014, on the campaign trail.

The Democratic National Convention is slated to be held in late July in Philadelphia.

This article originally appeared on NBCNews.com.