When Henry and his dog Mudge go with Henry's parents to visit Great-Grandpa Bill in the home with lots of other grandpas, they lead them all on a wonderful adventure.
For Henry and his big dog Mudge, spring means admiring the first snow glory, playing in puddles in the rain, and watching the five new kittens next door.
Henry and his big dog Mudge celebrate Henry's birthday with a pi?ata, a lively birthday party, and a cake shaped like a fish tank, making May first the best day ever.