Congrats to Chelsea Clinton and Marc Mezvinsky!
"Marc and I are overwhelmed with gratitude and love as we celebrate the birth of our son, Aidan Clinton Mezvinsky," Chelsea, 36, wrote.
She and Marc, 38, are also parents to 1-and-a-half-year-old daughter Charlotte.
"We are overjoyed to be grandparents again with the arrival of our grandson, Aidan Clinton Mezvinsky, born on Saturday, June 18, 2016," Bill and Hillary said in a joint statement to E! News. "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."