Buying cats

I love cats and wanted to keep them for a long time. I had come across a difference of opinion online regarding permissibility of buying cats so I bought one from someone whose cat had a litter. I told him that my intent was not to pay the price of the animal rather compensate for the food and care he had already given and he agreed.
I have read that majority of scholars deem buying cats is permissibe but the correct opinion is that it is haram.
Have I committed a sin by buying this kitten? Do I have to give it away? My family has become quite attached to it.