Regulating Enzo's temperature

We're hoping we'll figure out how many clothes to put on Enzo in this heat. We keep taking his temp to be sure we're not overheating him. In one of our classes, they told us that we should dress him in one extra layer than what we would be wearing. When it's 100 degrees, I'd rather not have any clothes, so it makes it difficult to decide how to dress our baby!

Today, we had him in a t-shirt and a diaper and after lounging in his vibrating papasan (with a crotch strap/saddle-thing), I went to change him. I screamed for Jeff when I saw what looked like deflated testicles. Did I completely destroy our son's reproductive organ? It looked like they had gotten punctured and all the air had been let out of them. Laughing, Jeff said that it was because he was hot and his testicles were trying to escape the heat. Seriously, I have obviously not been around little boys -- or didn't pay close-enough attention in sex education to know this.