Who did the boy say would come to repair the window?

A young boy was playing with a ball in the street. He kicked the ball so hard that it broke the window of a house and fell inside. A lady came to the window with the ball and shouted at the young boy. The boy was frightened and ran a-way.
    A few minutes later he returned and knocked at the door of the house. When the lady answered it, he said, " My father is coming to repair your window very soon. "
    After a few more minutes a man came to the door, tools in hand. The lady let the boy take his ball away.
    When the man finished repairing the window, he said to the lady, "That will cost you exactly 10 dollars. "
    "But aren’t you the father of that young boy?" the woman asked, looking surprised.
    "No, "he answered, equally surprised. "But aren’t you his mother ?"