Dr. Stone is a supporting character in the special adaptation of Madeline in London. She is the London veterinarian who checks Picadilly's health by checking his eyes, to find out he is only asleep and has the girls, Pepito, Miss Clavel, and Simon help her get him up. She tells them not to feed him green apples (it is unknown if she meant "unripe" or "Granny Smith") or roses, only grass and hay. They promise it.
In the book, the vet is an unnamed man.