I think the thing about their feathers insulating them from heat is more of a curious possibility than anything sound. I would imagine. Mine always look for the shade and the water in the heat. Even in the winter it gets hot during the day, and there they are, in the shade. Baby anythings have more difficulty in controlling their body temp, so it´s good they had your dh out there keeping an eye on them.Yesterday dh was baby sitting for me outside while I got our lunch, and when he brought the gozzies back inside the Toulouse "Babe" was panting and could not get cooled down, our temps were pretty warm 85* he acted distressed I took him out and put him into the pool he washed and cooled down and stopped panting. This is the 2nd time this has happened. Worried me but i wonder if it's because they are still only downy and they don't have that insulation yet that protects them from the heat. They weren't out in the blazing sun either.
Oh and by the way, they still are not interested in Missy or Sam. Missy really likes them and wants to hang out with them but they pretty much ignore her. Sam really doesn't seem that interested. I am now wondering if they will ever form a bond with the adults?
As for them taking to Sam and Missy.....they´ll most likely make a flock as they get older. But you´re their 'mom'.