Thanks for your question and good evening.
You would have to motion the court to reopen the estate.Once reopened here then you would have to deposit this in an estate account and then disburse it to the legal heirs
.There is no other way to legally deposti the check.I wish I could tell you otherwise.
As far as your mother here same scenario in her estate.This is why some lawyer advise against closing an estate and also the estate account leaving the minimum in it so that if this happens it is much wasier to deal with.
Again I wish I could tell you otherwise here but this is the procedure to deal with an after acquired asset here.
Law for reference.
Upon the petition of any interested person, the court, with such notice as it may prescribe, may order the estate of a decedent reopened if other property is discovered, if any necessary act remains unperformed or for any other proper cause appearing to the court. The court may reappoint the former personal representative, or appoint another personal representative, to administer any additional property or to perform such other acts as are considered necessary. The provisions of law as to original administration apply, in so far as applicable, to accomplish the purpose for which the estate is reopened, but a claim that already is adjudicated or barred may not be asserted in the reopened administration. [1969 c.591 §190]
You are going to need a local lawyer to do this here if you want to cash the check.