Hello and thank you for your question. Depending on how much money was involved, it may be that the will now actually want to proceed with court action, which can be complicated and expensive.
That issue aside, your situation is somewhat legally complicated. Initially, it appears you had a simple contract for the sale of the pup. Whilst they would not, ordinarily be entitled to a refund once they'd agreed to purchase, only the dog, but conversely you would not be entitled to retain the dog, unless you did so only because they directed you not to deliver it or refused to pay for its transfer as required under the original agreement. If the above is correct then you should be entitled to keep the original purchase price.
However, they may be able to argue that they should have received the resale value of the dog if it was viable to sell it after they reneged on their purchase agreement, less any costs of feeding and caring for the dog after it should have been off your hands, so they may have a claim for the value of the dog which you failed to realise because you decided to simply give it away. They would have to prove you could reasonably have sold it and at what price in order to claim.
Unless the dog is worth a considerable amount of money, it would seem unlikely that they would ultimately bother pursuing such a case, but I trust the above assists your understanding of what the issues would be if the matter is disputed, which may help you formulate a reasonable settlement if you are inclined to try to settle.
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