I got my cat Spetter from a cat home. He was said to be 2 to 3 years old, but by his looks and behaviour I thought him to be 1 year or younger. However, 2 more vets have examined him and were sure he was 2, maybe even 3 or 4, years old

Then why does he behave like a little kitten?
When he wanders out of our sight, he will start crying untill we call him and he comes towards the sound of our voice and ´finds´ us again. It is not enough to make just any vocalisation, we have to call his name and soothe him.

He also wants to sleep quite close to us, preferably on top of me, and he always takes a pillow or cushon to cuddle up against. He sleeps with his front paws on top of the pillow or cushon - or me.

When I stroke or cuddle him, he will have every appearance of thoroughly enjoying it, in fact, he will come up to me to be cuddled, but all at once his entire posture changes and he will viciously attack my hand. He really looks scared/ angry then. It is over within seconds, a minute tops. Then he is back to his normal loving, cuddly, dependent self.

I don´t quite know what to make of it. He is very small and young-looking for his age, as if he is developmentally retarded. But he is ever so clever in some ways. He figured out the cat flap in no time, he even knows how to get through a magnet-operated cat flap without having a magnet on his collar.

Some of the behaviour is insecurity. Especialy the kitten behaviour. Also the attack on you when stroking (I had a cat who did that) is him suddenly being scared of relaxing so much. (I assume he has been neutered?). I think that a lot of love and patience is called for. Although if it doesn´t improve there are meds that can help.

Hey there. If Spetter was separated from his mom at a very early age (and it sounds like he might have been if he´s physically and emotionally below average) then he may never have learned to let go of those kitten behaviours. it´s doesn´t mean he isn´t clever just that he´s having a hard time growing up cuase he was never shown how to behave. You will have to help him learn to grow up and become less dependent. You can start by making sure he knows you´re the boss of him. Ration his petting - don´t pet him when he asks for it. Pet him when you call and he comes to you and you initiate it. Stop petting after a few strokes and before he can become aggressive. Have a soft toy handy when you pet him so if he becomes aggressive you can give him that in place of your hand. In all things (feeding and treats as well) make sure you´re the one to decide when he gets them, and make sure you don´t give in to any of his demands.

If he does seem to suffer from extreme anxiety, then there are meds that can help him as Marketa suggests. And it will take some patience and consistency on your part.