Baby D usually wears a cotton sleep sack to bed. We keep the a/c on so his room is about 72...but it can get up to 74.

Well now we're on vacation with no a/c and it's pretty hot in here...high 70s maybe? I put him in his sleep sack but now I'm worried he's too hot.

How hot is too hot for your little one? If they don't wear a sleep sack, what do they sleep in?