You need to determine where in the esate administration process your mother's estate is currently. More importantly I would recommend that you obtain assistance of counsel in Florida since the rules do differ from state to state. An accounting of the administration is generally required and your opportunity to express issues should be available.
Consult sooner than later with probate counsel to act on your behalf.
The information you obtain herein is not, nor is it intended to be, legal advice. It does not establish an Attorney/Client relationship. You should consult an experienced probate or estate attorney for individual advice regarding your own situation.
I agree with my colleague. I would also point out that because you have posted your question as a PA matter, most Florida lawyers will not see it. You should consider re-posting using a Florida location, for Florida specific answers. You do not say if your sister is represented by legal counsel or not. If she is not, she should be. Rather than send a letter to the judge, you should consider legal counsel of your own. That will help you to understand the probate process in Florida, as well as whether your sister's actions should be challenged.
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