A time for celebration! Chelsea Clinton welcomed her second child, a baby boy, with husband Marc Mezvinsky, on Saturday, June 18.

“Marc and I are overwhelmed with gratitude and love as we celebrate the birth of our son, Aidan Clinton Mezvinsky,” Clinton, 36, tweeted on Saturday.

Her parents, former president Bill Clinton and presumptive Democratic presidential nominee Hillary Clinton, shared a statement about the exciting baby news as well.

“We are overjoyed to be grandparents again with the arrival of our grandson, Aidan Clinton Mezvinsky, born on Saturday, June 18, 2016,” they said. “We are all over the moon as Chelsea and Marc welcome Charlotte’s little brother to the world and grateful for our many blessings. Chelsea and Aidan are both doing well and enjoying this very special time together.”

Chelsea and Mezvinsky, an investment banker, are already parents of daughter Charlotte, 20 months. The new parents didn't explain the reason they chose the name Aidan, but coincidentally, both of their children's monikers are names of characters from Sex and the City.

Hillary told Us this past spring that she considers her role as “grandma” one of her favorites.

“Having this wonderful little person in your life makes you think about the future in a whole new way,” the Oval Office hopeful, 68, told Us. “Being a grandmother is the most amazing experience. And, of course, when you have the most amazing 18-month-old granddaughter, it’s even better. I arrange my campaign schedule around seeing Charlotte, and one of the highlights of the last year was getting the chance to have Chelsea, Marc and Charlotte on the campaign trail with me.”

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