[Not a little kid, but who is petulantly glaring with his arms folded right now? Vergil bites his tongue, however, knowing better than to point that out regardless of how...aggravating he's finding all of this. It's beside the point that he doesn't find the intensity of Nero's reciprocation of concern to be appropriate.]

I cannot speak for your uncle. I only know that the last time I can recall being ill was before my mother died, and I've little memory of it.

[It's not likely that Nero would exist if he had been prone to illness after that, but that is a fact he keeps to himself.]

Severe and significant injury has only ever posed a threat to my physical well-being for nearly forty years. And while I will concede that you struck well today, you haven't the power to do that much harm to me in a single strike as of yet. So, there is no reason to be worried.