My favorite to read to my little guys is _This is Not My Hat_ by Jon Klassen, which is one of the funniest, most subtle ones we've come across.
His books are superb! Short, sweet and extremely funny :D
I distinctly remember one day Skyping with my mother telling her how hard it was to find good kids books and using "A Sick Day for Amos McGee" as an example of a good one. I recited a few lines to demonstrate the language, "Every day when his alarm clock clanged Amos swung his legs out of bed and swapped his pajamas for a fresh-pressed uniform"... my daughter, to my surprise (not yet old enough to talk at the time) rushed into the other room to fetch the book.
My kids never got tired of me reading it and I never got tired of reading it. They loved that book. The illustrations are extremely well done. Who would draw bats wearing floaties?