Diarrhea of a Limpy Kid??

So my son did his very first book report on his favorite book.  Diary of a Wimpy kid.   This is the poster he proudly made.

My youngest daughter just couldn't get the title right and kept calling it "Diarrhea of a Limpy Kid."  I am not sure that book is on the approved book list.  Somehow Gumby, Living with Irritable Bowel Syndrome doesn't feel like a Newbery Award Winner.  What do ya think?