I have an eight month old male golden cocker spaniel.  He is absolutely lovely with myself and my husband.  But he had been a bit snappy with my eight yr old daughter.  He has previously snapped at her face when she has picked him up - even though she has been advised not to.  She cuddled him last week and he has growled and snapped at her - his tooth caught her face and marked her face and drew blood.  He is by no means a nasty dog, but I am extremely concerned that this could happen again.  Is there anyone who can offer me any advice.

It could be for any number of reasons but I would suggest a checkover by the vet to ensure he is healthy and well . He could have a tender spot somewhere which your daughter has touched when either picking him up and cuddling him ( or she could perhaps cuddle him too tightly) and thus making him snap. Even if its not that at least you can then rule it out and start looking for the root cause
Goos luck :)

Maybe she accidently hurt him when picking him up one day when you were not around? It sounds to me like he really doesnt like her picking him up so maybe make sure your daughter knows this and obviously never leave your daughter alone with him, if he gets the idea that she wont hurt him just by stroking him then i would have thought he will be ok.

These are just my opinions, someone with alot more knowledge will be along soon :)

Children should not pick up dogs.  Most dogs do not like being cuddled in the way that eight year old girls are likely to do it.  The only way to ensure that he doesn't snap again or start snapping or even biting for less, such as your daughter (or her friends) just walking into the room is to not allow her to do it anymore.

No dog should snap at a child or any other person for that matter, no child should pick up and 'cuddle' a dog they are not toys. So do some training with the dog and tell the child not to pick up the dog and teach her to respect the dogs right to eat and rest with out interference.