The father (never having seen an elevator) responded, "Son, I have never seen anything like this in my life, I don't know what it is."
While the boy and his father were watching with amazement, a rather heavy, not too attractive, older lady walked up to the moving walls and pressed a button. The walls opened and the lady walked between them into a small room.
The walls closed and the boy and his father watched the small circular numbers above the walls light up sequentially. They continued to watch until it reached the last number and then the numbers began to light in the reverse order.
Finally the walls opened up again and a beautiful, young woman stepped out. The father, said quietly to his son, "Go get your Mother".