John enjoyed playing bloody knuckles, he didn't care who it was or how old the other person was, he loved it. So the joy he felt when he realized his son had the same roughhousing personality was perfect.

Bashing knuckles together with playful intent. John smiled and collided his knuckles with yours, "Ye bleedin yet?" He asks, hoping to win this slightly violent game. He himself could feel his skin cracking up and getting ready to spill blood.