Not unless the document that established the ownership interests provides that. It would be relatively rare to have that kind of an agreement, but probably not unheard of. I would want to see it in black and white before giving her anything. It would probably be beneficial for you to meet with a probate attorney and determine exactly what you have, before speaking with her about how you are going to proceed.
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I suggest you find a real estate attorney in the county where the property is located. Some wil give you a free initial consultation. Either scan-in the original deed, will and probate documents to the computer so that they are ready to be emailed or have a fax available to send the documents (such as at an office store). Do not try to explain it over the phone. It is better for you to be well organized, make a phone appointment with the attorney and email/fax documents before the appointment so that the attorney has an opportunity to review them. He/she can probably give you a quick answer with the documents in hand. Good luck to you.
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