Steve knew that look pretty intimately, Tony wasn't as subtle as he pretended to be, and so he knew that he'd hurt Tony's feelings. He hadn't meant to, it was just surprise at the sudden ridiculous wake up call. He leaned over to look at the cake and snorted, lips curling up into one of his genuine smiles.

"I just didn't think you knew when my birthday was; heck, I didn't think anyone knew."

He opened the box carefully, even if had been dumped less than carefully, and ran a finger through the buttercream at the side to stick in his mouth like a naughty kid.

"Don't think I've ever had a birthday cake before."

Too poor when he was little, and then his Ma died and the war happened.