Double Panda-monium! Zoo Atlanta's New Twins

It was a high-profile, beautiful birth in our nation's capital today. The baby? A giant panda. Cute, seemingly cuddly, and yet these pandas may just be the least adaptable animals still on the planet. A species coming back from the brink of extinction with a little human help and a lot of human love. Last month at Zoo Atlanta, panda twins were born for the first time in the United States. ABC's Matt Guttenman has exclusive access as he takes us through the trials, tribulations, and dangers of being the world's most adorable and rarest bear. Squirming and squeaking, two fur balls. Virtually the size of a football. Nuzzling each other, impossibly cute. Brotherly love. Look at that. But also dangerously fragile. ABC News got exclusive access to the nursery of the only panda twins in the country. That should be illegal, that cuteness. Here at Zoo Atlanta and to their routine, in which a team of vets led by Dr. Haley Murphy weigh over three pounds, measure and examine these still tiny giant pandas. He doesn't even have any hair in his tail yet. Which for now, they're calling Cub A and, you guessed it, Cub B. This is extremely unusual. Very unusual. These are the only panda twins to ever survive in the United States. Ever. So, very unusual. And now that they're a couple months old. They are 37 days old today. That mean that they have a pretty good chance of surviving? We are very hopeful. Yes. Past the first week, we get more and more optimistic. Pandas are undeniably cute, but evolutionarily challenged. Biological carnivores who eat only bamboo. And they're even picky about that. The keepers will tell us what variety of bamboo they like that day, and they'll try and find that variety. But they'll also cut extras to have a little safety net. So, yeah, they eat a lot of bamboo. They are animals that can only breed once a year, during a tiny two-day window. Only 1,400 exist in the wild in China, coming back from near extinction. Is this A or B? This is A. With a lot of human help. And here in the U.S., there seems to be a mini-panda baby boom right now. At 3.36, while we were watching, while we were talking about it, we saw her water break as we were standing there watching her. At that point, a few more people came into the giant panda house, and we continued to watch her. And at 5.32, we had a giant panda cub born here at the National Zoo. At the Smithsonian's National Zoo in D.C., the panda, Bei Jiang, seen here on the zoo's panda cam, was in labor this afternoon, giving birth earlier tonight to a squawking little cub. The cub's making a lot of noises, is squealing a lot. And Bei Jiang is, again, being a poster child for a great panda mom. She's holding the cub and cradling it. And so at this point, everything looks great, and we're just, we're very pleased. In July, vets at Zoo Atlanta knew their 15-year-old panda, Lun Lun, was pregnant. But they only knew half the story. So how big was the surprise when you saw the second one come out? Well, we didn't believe it at first. One came out, and we were all happy, and she was showing the appropriate maternal behavior. And then another one came out. And we just all were pretty shocked, and the room went silent. And then we went and right away took the one cub out, because she didn't know what to do. She doesn't know what to do with two cubs. What ensued was a breakneck, full-scale mission to save both cubs. It had never been done anywhere. All pandas are technically owned by the Chinese and leased to American zoos. So a Chinese vet arrived for the birth and ended up sleeping in the nursery to ensure the cutest two furballs on the planet survived. Panda cubs emerge as helpless, about the size and shape of a stick of butter. No functioning eyes or ears, no fur or ability to move on their own. These images from Zoo Atlanta show their maturation, the wiry first hair, their body taking shape, and eventually they become cuter. He's trying to suckle me. And now, 38 days in, really cute. The microenvironment, the humidity, the temperature, everything has to be done. We have to stimulate them to urinate and defecate. They can't do anything on their own. But the vets here are so zealous about their baby panda's biosecurity, there's a strict sanitary regime. We're going to have you wear special scrubs, shower in to wash off any germs. Every time you go in and out, you have to shower. Yes, and we're trying to keep them as safe as we can. The cleanest doctors around. I did as I was told. All right, all refreshed? I'm totally refreshed. Then the whole ABC News team had to slip on booties. It went better for the crew than it did for me. Was I supposed to not sit there? I hope you're rolling on this. Inside the nursery, rubbing alcohol flows freely, for hygiene, of course. And you'll need to take your watch off, too, because we don't know where that band's been. We use this on our hands almost constantly in here, because it's really strong, it kills most things. Each cub gets a few hours with mom, Loon Loon, before he's swamped out and eased back into the incubator. It is undeniable, they are irresistibly cute. Oh, I have stretch. I even got to lend a hand. They're not soft. No. Trying to flip them over? No, just feeling his tummy. So, Amy, you want to help me with the measurements? I can help you. You can help me? I'm not letting go of the panda. Okay. So just hold him steady, right? Do you want me to physically hold him down? Well, he's not going to jump or anything. Okay, just like that. Just make sure he doesn't go off the table. The other thing we need to do before we put him back in is get his temperature. Can you hand me the? Great. Is it the same way? Is it the same way you take a baby's temperature? Okay. Well, I don't know. How do you take a baby's temperature? In the butt? In the butt. No. Okay. We do the armpit. Oh. When they were really little. It's much more humane. So you're one of the only people in the world who's ever touched a baby panda. It's an amazing thing. Is it hard not to become attached to them? Oh, we're all attached. Right? I mean, I miss them. We haven't had a lot of days off, but when we do get a day off, you really miss them, and they change every 24 hours. Yeah. They change so much. So when you come back from a day off, they're totally different. What Murphy says she doesn't think about is their names. According to Chinese tradition, pandas are only named when they're 100 days old. Do you guys have a favorite name? A and B. That's a good one. That's our favorite name. So Murphy isn't going there yet. For Nightline, I'm Matt Gutman in Atlanta. Cubs A and B won't make their public debut for a couple of months still. Here's hoping that they're healthy and thriving, if not for us, then for our kids.