Shocking, I know.
However, they do know what lightsabers are; they're swords.
So one day Ireland and Scotland are having a lightsaber duel as they're prone to and things are progressing as usual.
(This particular duel involved two lightsaber apps on various webOS phones.)
As they're swinging their phones around (and not touching each other in any way; with a good distance between them), my son raises his right hand, back s it up and them does a "force attack" against his sister.
Ireland is thrown backwards against the couch and ends up on the floor.
She looks up at Scotland (who didn't lay a finger on her), looks at the ground, and wonders how in the world she ended up there.
Meanwhile I'm sitting on the couch wondering why I hadn't been filming this entire thing.