Yesterday I posted a video featuring an adorable duckling who couldn't keep its eyes open. If you enjoyed that, well, you're in luck. I've found a whole treasure trove of sleepy-animal videos.
WARNING: Don't watch these if you're at work, or you won't get anything done for the next hour.
Ok, I'll stop there--but you can watch even more because Animal Planet has put together an entire playlist of adorable sleepy animal videos.