Well, bearing in mind the amount of money you have spent on these kittens i would say they are rightfully yours now anyway. If there is no contract (or similar) between you and the original owners then they cant take them back from you - or so i understand

You took the kittens on when they decided to leave the country, therefore i believe they lost all rights when they gave the kittens to you.

I think the next thing i would do is write them a letter / email stating all this and the amount of money you have spent and that the kittens now belong to you...............

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My little angels....Alfie, Bella, Barney, William, Baxter and Audrey


Rest in peace Barney my angel, i miss you every day