The former first daughter welcomed the new addition on Saturday.
It's a boy!
Chelsea Clinton has welcomed her second child, a baby boy named Aidan.
The former first daughter and her investment banker husband, Marc Mezvinsky, announced the newborn's arrival via Twitter. "Marc and I are overwhelmed with gratitude and love as we celebrate the birth of our son, Aidan Clinton Mezvinsky," Chelsea wrote.
NEWS: Chelsea Clinton is Pregnant With Baby Number Two
Little Aidan joins adorable big sister Charlotte, who will turn two in September.
Chelsea, 32, is the only daughter of former President Bill Clinton and presumptive Democratic presidential nominee Hillary Clinton. In a joint statement obtained by ET, the couple said they were "overjoyed to be grandparents again with the arrival of our grandson."
NEWS: Bill and Hillary Clinton Are 'Over the Moon' Over Charlotte
"We are all over the moon as Chelsea and Marc welcome Charlotte's little brother to the world and grateful for our many blessings," they wrote. "Chelsea and Aidan are both doing well and enjoying this very special time together."
Find out more about Chelsea's pregnancy in the video below.