More proof that I get my sense of humor from my father

My sister is at camp, and apparently she wrote my dad a letter that said something like:

"Dear Dad, I have nothing to say but I am writing you this letter because they won't give me dinner unless I do."

I used to go to a camp where you had to write a letter home once a week to get into dinner, so the letter makes sense to me. But here was my dad's letter in reply:

"Hello there, I have nothing to say either, but I am writing back to you because Mom won't give me dinner unless I do."

He said that my sister wasn't even sure it was a joke until they spoke a few days later, but it sure cracks me up.