What's in a name?

I had a cousin called Margaret - except that nobody called her Margaret - she was known to everybody as Peggy.  But it's only recently that I've realised that this wasn't some personal fad on her behalf, but that Peggy or Peg is an accepted nickname for anyone named Margaret.  But why?  It seems that it was a very popular name in medieval times and as it was a bit of a mouthful, it spawned a whole series of nicknames, including Maggie and Meg.  Meg became Peg, and there you go. Perhaps the most unusual of the various nicknames is Daisy.  This is a bit more obscure and relies on the fact that margaret was at one time the common name for the flower called the ox-eye daisy.  God bless, Peggy - I miss you.