They're royals: subtle gestures of respect are how they roll. It makes her status just as clear, in fact, as appending a title to her name might've done.

"The pleasure is all mine," he replies with a nod of his own, all long-ingrained graces and easy formality.

And then, because it really doesn't feel sporting to leave a small child face-first in the snow, he takes a few steps over to pick him round the middle and set him on his feet. The child's all diffidence for a full moment there, starts to leave...and then tosses one last parting snowball that spatters against Arthur's boots.

"For," Arthur chooses to belatedly amend, walking back to Sonia with a long-suffering look, "present company only."

Meeting impertinent children was not a pleasure!!! And if he thinks otherwise, he'll never admit it.