In PA if she had given it to your wife in a will, she would have had one year to file a law suit against your wife but since it was not given by will she may be able to bring a law suit for something called “tortious interference with inheritance.”
She would have to persuade a judge that the great grandmother told her that she was going to leave the ring to her but that your wife used fraud or undue influence to prevent the great grandmother giving her (the grandmother) the ring that if not for your wife's conduct she would have been given the ring.
The difference between going after the ring if it was given by a will is that with the will option she would have been bringing a claim against the estate
which would be barred under the statute of limitations but this way she can sue in civil court and ask for punitive damages paid to her from your wife.
Your wife of course gets a chance to present her side of the story to show that she did not commit fraud or use any kind of influence to get her great grandmother to leave her the ring. The judge will then decide.
I know it must seem crazy that she can even bring a law suit after all of this time but PA didn't put a limit on when such a law suit can be filed unfortunately and I am obligated to tell you the truth. So now you can be prepared if she does come and know what you need to prove. I hope this helps clarify and let me know if I can help further.
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