An interesting aside, does anyone know who the world's first exploited royal child was? Princess Elizabeth of York, or "Princess Betty" as she was fondly dubbed by the press in the 1920's. She was a media darling extraordinaire. Recall that after WWI, the royals were forced to reshape their image and their roles. There was also the rather odd business about the Prince of Wales, who'd rather drink and smoke with vulgar American woman than get down to finding a suitable English aristocrat and having little heirs. Then there was the Wallis Simpson scandal. So with all of this, the Queen Mother saw her darling as a way to reshape the image of the monarchy. She sanctioned books, new articles, photos galore (the approved of every sugar-coated word, to be sure), and loads of memorabilia. But make no mistake, Princess Elizabeth was sold out much like the Dionne Quints or Shirley Temple. The Queen Mother loved the attention. No other royal child was sold out like this, but since the press was so fawning at the time, and it was all so carefully controlled, nobody saw the harm in it.
The Queen Mother herself laid the groundwork for the "exploitation" of royal children. To be fair, she could not have foreseen the world nearly 100 years later and her great-great grandchild being subject to things like Instagram and Twitter, and the not-so-fawning press.