four hours. >> sounds exhausting. >> it's been exhausting but with this cuteness you can't begrudge any long hours at all. >> reporter: keeps you going? >> absolutely. >> reporter: the atlanta is one of four in the u.s. born with pandas. >> even though they were born here they still belong to china. having them here helps to us raise the money to conserve them in china. >> reporter: and china is where the twins will end up in a few years. until then they'll be in the care of doting doctors and staffers. >> a has a little bit thinner band over here on what we call the saddle. compared to b, oh my goodness. >> reporter: who can't get over these sweet, little faces. now back out here live, xilan looks to be hanging out with his dad, who is on the other side of that wall. it will be a while before the actual baby cubs will be out in this exhibit area and by the way, they will be named when they reach the 100 day mark, that's in line with chinese