In which the punchline doesn't, technically, have a whole lot to do with the intro. So sue me.
The girls are, of course, completely bilingual. They're equally comfortable in English and Spanish, although they do tend to intermingle the two as a kind of shorthand here at home, knowing that they'll be understood if they don't take the extra couple of moments to locate the specific English word for a concept they're used to discussing in Spanish.
But when they do that, it's conscious and passes semi-unnoticed. It's a habit that may endure well into adolescence, for all I know; but the older they get, the fewer and farther between are such moments of awesomeness as this:
Julia: Mommy, why don't you buy some panner solos?
Me: Some what?
Julia: Panner solos. You know, to use the sun.
Me: Oh, solar panels.
[Endeavors to explain...]