The little hedgehog I posted about a week or so ago has died. Mum contacted the rescue centre to ask after him and the lady said even though he was given fluids and put on a hot pad he never warmed up. She said this is often a symptom of slug pellet poisoning.
Please, please, please, please, please, if you garden don't use slug pellets (I'm sure most of you don't already anyway!) It's so sad that such a lovely little creature died just so someone's lettuces didn't get nibbled.