You have a sister as well? Is she younger?

[Celestia hardly seem like the little sister to Elsa, it makes more sense for her to be the older one.]

Rulership? I was aware of your royal lineage, but I was under the impression that you were a Princess-... Ah! Is Equestria a principality then?

[Her pale cheeks get a pink tint as embarrassment at herself for being surprised for a second fills her. She had just assumed that it was a kingdom or a queendom.]