Leo the Late Bloomer by Robert Kraus with illustrations by Jose Aruego.
Another favorite from childhood. I remember the librarian at Page Elementary reading this to us. It's a charming story of a tiger that doesn't develop as quickly as his peers. One of his parents is a little anxious about it and the other not so much.
Like most good children's literature is a none-to-wordy, simple story that makes a great point stated somewhat obliquely yet still clearly. One additional word of text wold be one too many but one less would be one too few.
