Flynn or Flyer? Your guess is as Good as Mine

My son has a strange predilection.  I have no idea how it has come about, nor what to do about it, therefore the only sensible thing to do is tell everyone about it.  A problem shared is a problem that other people can laugh at you about, as they say.

It started fairly early, about as soon as he could speak really.  His vocabulary, despite evidence on this blog to the contrary, is pretty limited, he can say 'digger' and 'up' (which for a while was a stand in for any sort of directional command.  Watching visitors struggle with how to get him higher as they were squashing him up against the ceiling while he was bellowing 'up' at them was for a while one of my guiltiest of guilty pleasures, he has now learnt 'down' as well, so so much for that.)  'Bird' has also been a particular favourite of his.  But one word has stood out above all others as his go-to word in almost any circumstance. It displays a singleness of mind, as well as such strange taste, that I find a little worrying.