Elsa doesn't know why she asked that. Waiting for a sign, perhaps, that Anna's happy and has moved on without her; that whatever beat her heart is thumping now needs to be silenced.
Some vindication that she did the right thing in refusing Anna in the first place.
But Anna doesn't say that. Her thumb rubs against Elsa's belly, and Elsa looks up only for Anna to duck her head, blinking.
"I... haven't had the chance to find out..." Anna says softly.
"Do you want to?"
"What?"
"Do you want to find out, with her?"