That cry came from no one but Arthur, the illegitimate son of Duchess Igraine.
You promised me something. What is it?
King Uther, however, did not have a child, and worried that if he were to die, there'd be no heir. But this morning, he'd heard the cry of a new baby, and he suddenly thought of a new idea: Steal him!
Hey look! A sword in a stone! Just what I need for the tournament.
So Uther goes to the source of the cry, which Uther's good at since he has a very good sense of smell.
And so Uther steals the baby, and he names him Arthur. Only while walking back to the castle, he realized that he didn't want Arthur. So he gave it to Merlin, a wizard, who gives it to Sir Ector.
A few years later, Arthur was walking in the forest when he found a sword. In. A. STONE!!! He pulls the sword out, and immediately became the rightful king of England without knowing it! More adventures coming up soon!