Formerly Conjoined Twins Mark 1st Birthday at Childrens National

Earlier this month, 1-year-old twins Tyler and Tyson celebrated their first birthday at Children's National with their siblings, parents, grandparents, and great-grandmother. Their family calls them "miracle babies" for good reason -- they were born conjoined, attached at their chests and bellies. They shared a liver, and Tyson needed heart surgery. At two months of age, Tyler and Tyson were separated in a complicated surgery that was aided by a plastic model of the boys' entire midsection made with a 3D printer. Their birthday party was a reunion with the Children's National doctors and nurses who were part of their live-saving surgery.  Watch the story on NBC4.