Whipping around to look for the source of the familiar voice, and spotting bright red hair, Bucky responded on what was likely a very him-specific instinct. "Natasha?"

Then, he pauses, not quite sure what to make of the person he's looking at. Same red hair, sounds just like her, but maybe four inches shorter. Looks like her, and doesn't. They could be sisters.

Or this is another Rick Jones situation, and Bucky's addled minded is telling him that everyone looks like the people he's looking for. (God bless you, Steve, but he's met Rick Jones. They don't look a thing alike.)

"Sorry. I thought-- never mind."