The father wanting to show the son that he can play in the sea, he took the son in a boat in the deep waters. As he was playing turning and twisting the boat, the boy felt out of the boat. The father jumped inside the water to save the son, in his surprise the son grabbed tight in the fathers genitals. Then the father starts swimming towards the boat, when the were inside the boat, the son says:

-Daddy thank you, you have saved my life.
The father replies:
-you see, if it was your mother you would have died.