Isaac and Ari went to camp.  I mailed them cards before they left because it takes a while for them to reach the camp.  I received a card from Isaac from Canada, not long after he left.  When they returned, I spoke with both and thanked Isaac for the card.  I told Ari I was aware he had sent his aunt a card.  He said that he did not have time to write this year and reminded me there was one year when he sent no one a card.

I choose to let this pass.