In most cases the Executor of a Last Will and Testament is required to provide a report to the probate court regarding the administration of the estate.
If an asset listed in the Will cannot be located, that asset would be included within this report.
The report may generally indicate what items of property were located and sold/distributed per the terms of the Will.
The stated beneficiary of the missing asset need not always be notified of the existence of any particular asset; there may probate court local rules regarding such a missing asset, but in general such specific reporting would not be required.
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