"We are overflowing with love and gratitude," the children's book author tweeted.
Congratulations are in order for Chelsea Clinton!
The former first daughter announced on Monday morning she and husband Marc Mezvinsky had welcomed a son, Jasper Clinton Mezvinsky. This is the third child for the couple, who married in 2010.
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View Story"This morning we welcomed our son, Jasper Clinton Mezvinsky," Clinton, 39, tweeted. "We are overflowing with love and gratitude and can't wait to introduce him to his big sister and brother."
Jasper joins the couple's son, Aidan, 3, and Charlotte, 4.
Clinton's mother, former Secretary of State Hillary Clinton retweeted her daughter's news and wrote, "Sharing some happy news this morning! Bill and I are so thrilled."
Similarly, Clinton's father, former President Bill Clinton, also reshared the exciting news and added, "Hillary and I are overjoyed and grateful to meet our new grandson, Jasper!"
Another person who commented about baby Jasper? Singer John Legend, who tweeted his congraulations to Clinton.
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View StoryClinton and Mezvinsky revealed back in January that they were expecting their third child.
"Marc and I have loved watching Charlotte be such a wonderful big sister and we're excited to watch Aidan become a big brother!" Clinton tweeted at the time. "We cannot wait to meet our newest addition later this summer."
Earlier this year, Clinton expressed how being a mom inspired her to become a children's book author.
"[My kids] love being read to and talking about what they're reading in books," she told People in October. "Particularly for young readers, books are not only a way to help break down and communicate ideas [but] stories of real empowerment."
Check out the Clinton family tweets below.
This morning we welcomed our son, Jasper Clinton Mezvinsky. We are overflowing with love and gratitude and can't wait to introduce him to his big sister and brother.
@ChelseaClinton
Sharing some happy news this morning! Bill and I are so thrilled. https://t.co/199K5REg8G
@HillaryClinton
Hillary and I are overjoyed and grateful to meet our new grandson, Jasper! https://t.co/vN1tHDFgv9
@BillClinton
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