Why the boy from Prostokvashino called the uncle Fedor?

"What of the little boy the uncle? " or "If he is an uncle, where his nephew? " — such questions quite often set users of social networks, having faced Edouard Nikolaevich Uspensky about Prostokvashino and the uncle Fedor. Actually versions of an origin such, not on age of the valid address to the child there is not a lot of, but for a start the small reference. What do we know about this work? The fantastic story "Uncle Fedor, Dog and Cat" was published nearly 50 years ago. In 1974 Edouard Nikolaevich Uspensky was published by JOINT-STOCK COMPANY "PUBLISHING HOUSE "DETSKAYA LITERATURA". In a year the animated film of the same name came out...