She would do the same were the roles reversed.

[ He huffs a laugh. Of course there's no malice or judgment in his voice when he says so; it's simply knowing his twin like he knows himself, and understanding that their rivalry is borne of a deep love of each other.

Who else can you tease if you can't tease the one closest to you?

That said ... ]

But I do try to mind myself, particularly in front of company. You spoke earlier of your family. Do you have siblings as well?