Surfer Boy Bill
In 1931, Pathe caught wind of a toddler water skiier who was wowing professionals. Bill was four years old but could already ride the choppy waves at a fast pace. Some suspected it was a hoax and so a titlecard was inserted saying "He's a real boy! Watch him do his stuff!"
81 years later we've no idea what Bill did with the rest of his life. We don't even know Bill's second name. But you can still watch him doing his stuff here in the British Pathe film Cutie: