Panda Baby 2012: Panda Cam Catches Mei Xiang And Baby, Who Is 'Still Similar In Size To A Butter Stick' (VIDEO)

WASHINGTON -- The Panda Cam has delivered up the closest look yet of giant panda Mei Xiang with her new teeny tiny cub.

The baby was about the size of a stick of butter when he or she -- we'll know which, hopefully, in a few weeks, when vets are able to do an official exam -- was born on Sunday night.

Zoo spokesperson Jennifer Zoon tells HuffPost DC that until that exam, "we won’t know exactly how much it’s grown."

"However, keepers have seen and heard it nursing," Zoon said. "So we know that it is in fact growing, we just can’t tell by how much quite yet. It’s fair to say that it is still similar in size to a butter stick until we know more."

Be sure to spend all of your waking hours watching this new family on the National Zoo's Panda Cams -- the only way to see them just yet. Here's a link to one of the Panda Cams and another. You can also watch from your phone, using the National Zoo's app.

And check out the Flickr pool of Panda Cam screen grabs showing the baby, too.