This would depend upon what type of return they are filing. ProSeries Basic can complete a 1040 return, even for a deceased individual. However if they need to file a 1041 or 706 then that return is not available in ProSeries Basic but can be completed in ProSeries Professional.
As a ProSeries Basic customer you automatically have pay-per-return access to download and use ProSeries Professional. You won't be charged for anything until you try to print or e-file from it.
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