Photo via Smithsonian’s National Zoo.

We interrupt your regularly scheduled DCist posting to bring you this brief update on giant panda Mei Xiang’s twin cubs: The National Zoo says that both cubs are “doing well,” but they had a “challenging night.”

The Zoo is currently trying to make sure Mei Xiang spends an equal amount of time with her new cubs, but last night when they were trying to swap the cubs at around 11 p.m., Mei wouldn’t set the cub she had in her possession down. Subsequently, the Zoo’s panda team had to tend to the smaller cub with bottle feeding and, when they suspected it wasn’t getting enough volume, to tube feeding.

Despite this slight hiccup, they’re optimistic about both the cubs’ survival. Still, as the Zoo notes, “newborn cubs are vulnerable and this first week is incredibly important and the risk remains high.” Right now, the panda team is working ’round the clock to ensure Bao Bao’s siblings are here to stay.

This has been a panda cub update. As you were.