bq. FLASHBACK: Frederick, Prince of Wales, eldest son of George II, was, by all accounts, a bit of an arse. His mum called him a beast and a monster. And his dad seriously reckoned he was “wechselbalg” – a werewolf. And then, in 1749, Frederick got smacked in the head by a cricket ball. Two years later he died of an infected cyst in his head, leaving the way clear for Fred’s slightly mad son to become George III.
But a Wechselbalg is not a werewolf – that’s a Werwolf (as in the famous Morgenstern poem where the Werwolf wants to be declined – wer, wen, wes, wem – or as the Germans say, confounding my language-learning attempts, wer, wes, wem, wen). Wechselbalg is changeling. According to Hermann Paul’s Deutsches Wörterbuch – a dictionary well worth having: it doesn’t deal with the whole of the German vocabulary, but what it does deal with, it does thoroughly and in detail, with etymology and history – amazon.de link: Deutsches Wörterbuch
‘nach dem Volksglauben ein von Hexen stammendes untergeschobenes Kind, daher als Schimpfwort für ein mißratenes Kind gebraucht. Andere Bezeichnung Kielkropf’. (This is not the only German reference in the Guardian article).