It's important not to confuse two different issues. Early desire to write doesn't necessarily equate with early blossoming of talent. :)
From the moment I learned that stories were created and written by people and didn't appear in the world by magic, I wanted to be a story teller and a writer. I was, however, most definitely not a child prodigy. No one praised my story writing ability and I mostly kept it secret. In fact if I was praised for anything when I was small, it was my drawing. I did try to write my first novel at the age of 9 or 10, shortly after reading Black Beauty for the first time. I can still remember what it was to be about as well. Of course I didn't manage more than a page or two. Otherwise, though I was an avid reader, I was very much of a tomboy and played cowboys and Indians and running and chasing, as well as more traditional girls' activities like skipping, roller skating and two-balls. One way my story telling did manifest itself though was in the games I played, alone or with my brother, with our small model animals and soldiers. There was usually a narrative running through the games, such as expeditions to explore unknown territory, daring rescues or people/animals kidnapped by an enemy etc. etc.
I became more serious about writing through my teens, aided and abetted by a friend at school who also wrote. We entered a play writing competition and came ... nowhere. :) Thereafter I've always had some novel or other on the go, though progress was, of necessity, often slowed by producing children and having to earn a living.
In fact one of my problems with regard to writing right now is that I'm dealing with my failure to achieve my childhood dream. Would it have been better to have had no writing ambitions, and thus be delighted with a few short story sales scattered over nearly 20 years? Or is it better to dream and hope, even if you never achieve your ambitions?