Trivia: This was the last animated feature to be released while Walt Disney was still alive.
Trivia: Except for the prologue, the "Sword in the Stone" does not actually appear until 71 minutes, eight minutes before the film ends.
Trivia: This was the first Disney animated feature to be made by a single director.
Answer: Part of it is the cliche of the abusive or angry step-parent or adoptive patent. Although this is something that does occur, Sir Ector just thought more highly of his own son and would rather see his son become king. He probably regrets having to take care of him, but felt obligated as a knight of Uther Pendragon. In addition, he's more of a brute and fighter and doesn't like learning (or magic). So when Arthur displays an aptitude towards learning over fighting, Ector has less in common with the boy and treats him as a servant.
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