The siblings don't have to agree, though it would be best if they did agree to some kind of settlement to avoid potential litigation from the fourth.

If the executor proposes a settlement that one or both of the other siblings in the will don't like, they can always object to it and force a trial on the issue.

The executor should get WRITTEN agreement from the other beneficiaries. Otherwise, she must distribute a full third to the beneficiaries who do not agree.

The executor cannot legally force the two other siblings to include the fourth sibling in the distributions. If all three of the named siblings won't agree, the Executor would have to obtain an order from the Probate Court specifically directing inclusion of the fourth sibling and there would have to be a legal basis for the Court to grant such a request.

Depending on the amounts involved, if the three siblings agree on including the fourth you also need to be careful of potential tax issues as the inclusion could be treated by the IRS as the three of you having received your inheritance and then having made a gift to your sibling.

If you need further assistance, please do not hesitate to call us.

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