Thanks for all your comments everyone.
Yes I had worried re hyperlexia/ASD/receptive language impairment, etc. She seems to always have had an exceptionally long attention span that, reportedly, young children are not supposed to have.
Yes, 'gifted', is not always a gift and a worry in itself. I think, the magic word, 'normal' is something most parents would be most happy to hear about their child.
In answer to others queries:
She has been able to point to and recognise any letter in the alphabet since about 16 months and say what they are. (Mostly due to having been completely obsessed with the Alphablocks for about 8 weeks solid).
She recognises words within a well known story. (Whole sentences now - since my last post. I know this is mostly from memory but have read that this is the 'start' of reading). I also play games with flash cards where we have them face down and I ask her to find the 'queen' or the 'frog', etc. (The cards have just the word on the back - the picture being on the front). She absolutely loves this.
Yes, she has yet to understand fully the use of phonics and how to piece the sounds of each letter together to read an unusual word.
Thanks everyone. Sounds like she's normal (ish). So fine with me!
It was great to hear all your other stories.