Yes, DS wears either a tank style white undershirt (think old guy with beer gut style : ) or a plain white T under any shirt he wears. He grew up way South of here and claims that his body is just not built for this horrible, horrible climate and until we move he needs to keep himself warm. But he's a tad dramatic.
DD wears undershirts if needed, which is often. I find a lot of girls shirts are either to short and ride up on her belly or way to big in the neck. (even the H.A. shirts have big necks!) I get squeamish at the thought of her trotting off to school with most of her chest visible, so a little undershirt or a tank top solves the problem. Plus it keeps her warm - in agreement with my son : )
My other Ds's wear underarmour type shirts under their shirts, one because he's an athlete and often on the field in inclement weather, the other, because he's in awe of his big bro and wants to dress just like him.
My kids do in the fall/winter/spring. But not in the summer. DD wears a tank style and DS wears the crew t-shirt style.
Both of my boys wear ribbed tank tops every single day. They like the tightness of it for sensory reasons. It's very grounding to them.
Nope. We live in Canada...not the coldest part mind you
We do layers if its cold. I find undershirts annoying, because if it gets hot it seems weird to just wear the undershirt, where as, if you were wearing a t-shirt you could wear that with no problem.
It's normal for us to wear a t-shirt, then a hoodie, then a rain jacket.