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IRS Pub 559 --

"If the decedent accounted for income under the cash method, only those items actually or constructively received before death are included on the final return.

Income in Respect of a Decedent

All income the decedent would have received had death not occurred that was not properly includible on the final return, discussed earlier, is income in respect of a decedent.

How To Report

Income in respect of a decedent must be included in the income of one of the following.

• The decedent's estate, if the estate receives it.
• The beneficiary, if the right to income is passed directly to the beneficiary and the beneficiary receives it.
• Any person to whom the estate properly distributes the right to receive it."