Steve took the inhaler, his nailbeds a little blue from obviously not breathing that well a while now. But he was used to it. He was careful breathing out as much as he could before pressing down and breathing in the medicine. He did it a few times, because that's what you did when it was bad and your lungs were tight like a monster was sitting on your chest.
His eyes widened when Tony showed him The Arc Reactor and he mouthed the words that he'd never heard so he'd remember later. "You built that?" Steve asked in awe and admiration and like Tony was the most impressive person in the world (which he absolutely was). "Are you sick too?" He asked and he didn't mean to sound excited, Steve didn't want people to be sick but it might be nice not being the only one.
Steve was surprised to see that Tony had his medicine in the house, his mother would take him somewhere when she could afford it and never had the luxury of having so much. So Steve carefully and obediently rolled up his sleeve. "Are you a doctor, Tony?"