He understood what she was implying even if she didn't say so, but he doubted there'd be any day he just showed up without warning, if only because he valued his privacy and was well aware that Natasha did too. But he appreciated the sentiment none the less -- it meant a lot to know that she'd be willing to give up something for him, even if it was space.
There weren't a lot of people in this world (or any other, at this point) that could get away with touching him the way she did, even if it was gentle, it was familiar in a way he didn't often allow himself and Tony exhaled as deeply as he ever dared. There Natasha went again, looking for all the world like she understood exactly what he was going through. Maybe she did.
"That's what Steve said," Tony responded -- not really an answer to the question in so many words, even though it sort of was. He'd been told before it wasn't his fault, and he clearly didn't agree. He'd been responsible for Peter since the day he showed up at his house to recruit him to piss Steve off in some airport in Germany.
Peter had tried his damned hardest to deliver excellence at detriment to himself after that. And that was on Tony. And here, it was on him for not keeping a better eye out, for even allowing the kid to be in a house that wasn't his. "No," he decided. "Not really."