The estate of the deceased should be directed through a Probate Court proceeding shortly after death, with the property distributed per the Probate Court according to the terms of the Will.
From your question, it appears that Probate may not have happened at the proper time.
If the property in question is currently titled in the name of the deceased person, control or direction of the property may be difficult. And directing that rent be paid to a deceased owner may be difficult to enforce as well.
Since this process may not have been handled correctly from the start, we suggest you discuss the matter with a local attorney; you can find a local attorney for FREE at Standard Legal’s Attorney Find page.