Fresh air for sick toddler

My toddler has been sick for about a week with a cough, chest congestion, and a stuffy/runny nose. No fever and she’s acting fine. Would it be beneficial or harmful to bundle her up and get her some fresh air today? (In our yard, it’s about 50 degrees. not in public around other people). It seems like her sickness is on its way out and she’s dying to go out and play, but I’ve always heard such mixed things about that.