First and foremost, Dikkie Dik is a cat. Not a real cat, a cat who is the hero of a large number of very successful, funny and amusing children's books by Jet Boeke and Arthur van Norden. The drawings, by Boeke, are especially well done, simple and evocative.
So, if this series is so wonderful, why have you never heard of him?
Because all the books are in Dutch.
"Dikkie Dik" translates roughly into English as "Fatty Fat" - related word, "thick" - and the cat is indeed on the hefty side, but very very cutely. He is an orange cat, and appealingly plump compared to the other cats who appear in the books. These are books for very little children, so they are mostly pictures, with some simple text. There are even "block books" of cardboard for toddlers. Besides being highly amusing for tiny children, the books are very funny to adults, including this one. (In fact, making little children's books bearable by adults is an essential quality if the books are to sell, since it is adults, not children, who buy books.)
The little tales are short, and droll in a Dutch sort of way. In one of my favorites Dikkie Dik is reproved for peeing in a flower pot, and just in case we might miss the point, the drawing shows a yellow fluid leaking out the bottom of the pot and onto the floor as the cat sits amongst the leaves. I cannot remember an equivalent book in English for children this age (which is to say, about 2 - 5 years) which achieves this precise mix of humor and bluntness.... and besides, cats do pee in flower pots, though this is seldom discussed in books for English-speaking toddlers.
I love these books because I am trying to learn Dutch. When I started, they were about at my reading level, and a lot more fun that the usual beginning material for new languages.