I missed this tonight, since I was putting Livi to bed, but when I returned to help Ryan get the boys dressed in their pj's, he said "Well, Jackson asked me a really good question a few minutes ago."
Intrigued, I asked "Well, what was that?"
Ryan responded with a sheepish yet mischievous look on his face, "He grabbed himself down there and asked 'Dad, why do we have THESE,' pulling on his testicles."
Me: "And what did you tell him?"
"I asked him why he had a nose, and he said 'No, Dad, I said why do we have THESE.' "
Obviously he was not going to be dissuaded, so Ryan explained that they are called testicles. And went on to say that boys have them, but girls do not. Jackson's next question: "Do cows have testicles?"