What's in a name? You'd better ask Poo, Pants or Tubby On Friday my husband, or the man I like to call Edwardian Dad, will change moniker and personality for 24 hours. The world-weary paterfamilias will be changed into schoolboy dissident "Gus," who "contributed nothing to the community of the school," according to the headmaster, but who once cycled 26 miles in a snowstorm to buy a Fairport Convention album - so you can't say he lacked tenacity. The transformation will occur when we stay a night with Gus's old schoolmate "Vaughan Senior," who's been calling him fond names even longer than I have. No matter that in the 43 years since my husband left boarding school, no one else has Gussed him; childhood nicknames are even harder to dislodge than nits, reputations or spouses. Once coined, they never leave you. So the Prince of Wales needed to tread gently when he announced that his little grandson would be called "Georgie in no time." It's a sweet pet name, until you think of future tabloid headlines: "Kissed the girls and made them cry!" There again, it's possible that Charles wanted to divert a million minds from dwelling on the Madness of King George - although Mad George Cambridge has a certain pro-wrestling pizzazz about it. Either way, Prince Charles is used to nicknames. The infant William was known as Wombat, Harry is really Henry, while Camilla and Charles dubbed one another Fred and Gladys in the years before their marriage. All of which name-calling reveals something I have long noted: posh people are far keener on nicknames than the less blue-blooded. Examine the writing of key chroniclers of privilege, Nancy Mitford and Evelyn Waugh, and you'll uncover a host of Bunnies, Binkies and Bunters. My 92-year-old step-mother-in-law, an energetic member of the hunting, shooting and fishing classes, can sometimes talk in an inpenetrable code, where every key character is called Bundle, Rocket or Horse. Generally, the more privileged your education, the more likely you are to be called Stonker or Smuts. A colleague mentioned that one old Etonian pal was known to friends and family alike as Leper - undoubtedly on account of his charm. Public-school girls have the ironic pet name down to a tee. I've hardly ever met a gazelle-like former pupil of Benenden or St Mary's Ascot who wasn't known as something along the lines of Poo, Pants, Tubby or Canker. Although many would argue those are all better options than naming your child Candida, after a yeast infection. The state-schooled use nicknames too, but they tend to be insults from enemies - or treacherous friends. And they're less abundant now that traditional playground terms of abuse, such as Carrot-top, Four-eyes and Fat-boy, have been eradicated by anti-bullying measures. Among the middle classes, it's parents who establish the pet names. My youngest godson may be christened Luke, but his mother and everyone else calls him Bean. Our sons were playing with two old friends, Bertie and Teddy, last week and I was amazed to discover they were christened Robert and Edmund. But then who am I to talk? My sister Dorcas was christened Henrietta, my brother Hereward is known by many as Reg, while my husband and I struggle to stop calling our sons Monster and Beast. I dare say His Royal Highness Prince George of Cambridge will find a shorter, nattier moniker settles on his shoulders in due course. Mind you, it's the nickname he's given as a monarch that really counts. Looking back at his predecessors, you can see how much better it is to be remembered as "the Sailor Prince," like George VI, than German George, Farmer George or the Prince of Whales (George I, George III and the future George IV respectively). Prince William may fly search-and-rescue missions, but my advice for little Georgie is to join the Navy. The Helicopter Prince just doesn't have the same ring to it.