In our house, we have a saying. It’s not one that I created, but one that I heard Alex’s teacher say last year, and I fell in love with. It really does say everything that needs to be said when one of my 3 whiny kiddos is complaining about something. Today, Ian, my 3 year old, finished the phrase before his sister could get a word out, and I about fell over. The phrase goes like this: “You get what you get…” and the child is supposed to say back “…and you don’t throw a fit”. Very basic and easy, but I wasn’t quite prepared for Ian to smile and say his part. Granted he didn’t get it exactly right, but “…n you don’t frow a fit” works just fine for me 
At least I know that he’s listening while screaming bloody-murder!
We use that one, too. It works on my husband, as well…lol!
I actually considered stenciling that around our playroom…I say that at least 4 times a day at school, haha.