The vet has just phoned. They have moved Simba to their Pottersbar practice where the vet who deals with these sort of things is based. He has had x-rays and blood tests, the vet was very impressed he didn't need to sedate Simba as he is so well behaved.
They don't think he has a blockage, its probably Gastroenteritis. He is on a drip and they are going to start giving him little bits of food in the next couple of hours.
He may be allowed home late this evening, but it will more then likely be tomorrow morning.
Its very strange not having him here I keep looking behind me to see where he is.
Thank you all for you for you kind words. I'll let you know as soon as I hear any more or when he is home.
Simba'x Mummy xx