cry baby

Contrary to the actual words used, a cry baby neither cries nor is an infant, but is a fully grown adult who whines too much and should know better. A cry baby will normally complain about the most petty things, like there being no packets of brown sugar on their hotel room tea tray, the fact the train is four minutes late, and being dumped by their significant other. The only acceptable way to deal with a cry baby is to pretend to physically cry when they start complaining, by rubbing ones eyes and quivering ones bottom lip in a totally OTT manner, followed by the put-down "don't cry about it".