I'm planning a trip to Orange County, CA this summer. We are staying near the beach for a week. I need to buy a new rash guard shirt for DS (age 2) and would love to buy one with long sleeves but am wondering if he would be too hot? Our gym has a kiddie pool that we spend a lot of time there in the summer, so he will be using it a lot. He is just so fair skinned and I want to keep those rays away! Beach mamas, suggestions?