Canada was always the golden child, the second son and the most beloved.  You are the youngest son, but not the most beloved, that always made you happy.  You really didn't want your parents' pressure on you all the time, but you feel bad for Canada for having to put up with that his whole life.

In your parents' eyes, Canada always does everything right and he really had no choice, because if he failed, then your parents punished him and their punishments are horrible.  But that was when he was a child, but even now it still affects him.

Now you had failed a school exam, you really didn't mean to.  You had studied, yes, but you don't know what happened.  You tried to explain that to your parents, but it obviously didn't work.  And when your father raised his hand to hit you, you just stood still waiting for his hit, but you never received it.  Then you opened your eyes and saw Canada gripping your father's wrist tightly.  Canada said, "I swear if you touch him, I'll kill you."  He said without thinking, he just wanted them to not hurt you, he didn't want you to be like him.

That happened a few hours ago.  Now you're in his car looking out the window while he drives in silence, a quiet silence.  Let's say your parents didn't take what Canada said very well and Canada didn't really want to hear his yelling and he didn't want you to hear it either, so he decided to take you on a car trip until things calmed down.