who is a bear called Fred?

Sorry its taken so long to reply, Helen, - it's a reference to an old, tired joke about Bear parents whose new cub had very tatty fur, so they called him Fredbare.

It has, indeed, got a lot to do with the fact that I am a Londoner, by upbringing if not, strictly speaking, by birth. It is part of the London speech pattern to pronounce "th" as "f" if the initial letter or "v" if the final one.