It is unclear from your question how long the property has been in the name of the estate. You should consult a probate lawyer in California to get information about the specifics of California practice. However, generally, the executor will be the person named in the will. If there is no will, any family member or creditor may petition the court to be named administrator. The court should require notice to family members and then possibly have a hearing to determine the best person to do the job. Paying the mortgage shouldn't be the determining factor.
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