He invites his parents to play a strange game --- but that's not all!

First, he organizes a strange game for his parents, then he reveals the real reason why he went to so much trouble!

Initially, Joseph explains to his mother and father that it is very difficult to tie a shoe, especially if the shoelaces have been laced differently from the way they are accustomed to doing it. Then, he makes them both wear a blindfold and tells them that now they have to try to tie a particular type of shoe that he places on the table in front of them. 

Et voila! The shoe in front of each of them is a little baby shoe! Joseph's father immediately understands its meaning, while his mother is still concentrated on trying to win the game. Then Joseph tells his mother, "Do not worry about tying the baby shoe now, you still have seven months to learn!".