Mug Shot: Hippo Birthday

I found this mug at my daughter's house. And since yesterday was her birthday, this seemed like a fitting time to post it. I'm not sure where this hippo-mania came from, but this is the first of two hippo-esque mugs I saw there. 

Meanwhile, my niece is completely enamored with the "I Want a Hippopotamus for
Christmas" song. My sister is addicted to riddles, jokes and puns and would no doubt appreciate the lyrics on the back of the mug.