P. D. Eastman.
I remember this book vividly from my childhood and added it to E's collection sometime when he was first born. We started reading it when he was about 2+ years old and yes, the fish book, is still a popular choice. E's ever changing infatuations seem to breath new life into familiar titles and this time it's the fire truck scene that he waits for each read.
Otto is a seemingly innocent little goldfish that our young narrator purchases from one Mr Carp. Warnings not to overfeed him go unheeded and Otto soon grows out of his bowl, not stopping until he's bigger than the town pool. It's a wild frenzy of activity that takes places moments after Otto finishes his last nibble of food. He grows out of his bowl and is transferred to a vase, he grows out of the vase with alarming speed and is transferred to a giant pot. There's no rest for the wicked, however, and Otto is almost immediately too big for the pot. He's finally hoisted up by a fire engine in a final mad dash to get him to water and the last resort is the town pool. He's still growing though so Mr Carp is called in to save the day. He jumps in the pool and all we can see is the swirling, swooshing water and Otto's bright orange tail as it disappears beneath the waves. Finally, Mr Carp emerges, triumphant, with a gold fish bowl and Otto returned to his original size.
Originally published in 1961, this is a great story of a fantastical series of events that really gets children engaged. 'Look at that great big fish mommy!' is E's typical outburst when we get to the pool scene. The illustrations are detailed and effective, using a limited palette that makes Otto's bright orange stand out page after page. Otto's expressions are a study in the stages of worry and surprise and do much to bring him to life. This book was reissued more recently as an 'I Can Read It All By Myself' book and in my house it was haggled over by both a 3 year old and a 6 year. I can't help but feel as though E is a bit like my own little Otto, growing out of each pair of shoes, pj's and trousers almost faster than I can keep up!