Indeed that is the case. Behind doors she is far more open, and yes, she does tell quite a few jokes! (I don't know that I've ever heard of her whistling, though.)
Well, I am surprised. It just doesnt seem to be in her to be that way from what I've seen but I guess I'm wrong. Thank you for correcting me. I would hope she doesnt whistle as that is not very dignified for a Queen.