Hey Paddi, if you see this write back--I think my e-mails to you are winding up in the spam box.
(apologies to everyone else)
A retired family friend used to go camping with my brother and his young children, as each became old enough they had to acknowledge their mantra in order to be able to go: "no gasbags, no whiners". The phrase was also invoked during low or almost-whiny moments in the primitive conditions. They made some better humans with that philosophy. I use it with adults sometimes, and remind myself to suck it up on occasion too. Although the "put on your big girl pants" as the aunt of 6 is a better visual, for humor.