My mum always denies she said this but one time my younger brother and I were being hilarious (immature) and she said "stop all that cheesy piffle" and that was it for us, we were HOWLING with laughter, it just sounded so ridiculous coming out of her mouth. What is cheesy piffle? Can you eat it? Where do you purchase such piffle?
Another one is "pipe down" - I got told to pipe down by my parents at dinner once despite the fact I was being hilarious (immature) so I responded by playing air-bagpipes. They tried not to laugh but I won
