It was not very long afterwards that Michael woke up one morning with a curious feeling inside him. He knew, the moment he opened his eyes, that something was wrong but he was not quite sure what it was. "What is today, Mary Poppins?" He enquired, pushing the bedclothes away from him. "Tuesday," said Mary Poppins. "Go and turn on your bath. Hurry!" she said, as he made no effort to move. He turned over and pulled the bedclothes up over his head and the curious feeling increased.  "What did I say?" said Mary Poppins in that cold, clear voice that was always a Warning. Michael knew now what was happening to him. He knew he was going to be naughty.
P.L. Travers, The Rise of the Mafia : the definitive story of organized crime
boys, humor, naughty