help our little boy

My little boy had to be rushed to the vets due to cystitis (unable to urinate/blocked bladder). Wolf, he is 1 year old, is normally a happy and healthy cat. And he is loved very much and cared for. We are asking for any help towards vet cost. As we recently (2 weeks ago) had taken our other cat to the vets due to being attacked by a dog which we paid nearly £1000 in vet bills. And now our Wolf has been rushed in to cystitis we have paid over £900 in vet bills. The vet’s are asking for more….

We do have pet insurance but they will not cover the pre existing condition.

So please any help would be greatly appreciated.

Thank you. update he needs an op to allow him to wee again any help plz