It is very unlikely that probate will be avoided here but the title will need to be reviewed and the value determined before a final determination can be made. The reality is unless the property was in joint tenancy, probate may be necessary as far back as Susan's estate. A probate attorney can help with this. Remember probate fees are paid from the estate at the end of the probate so your friend does not need to worry about coming out of pocket for those fees now.
I agree that it is probable a probate proceeding will be required. A quiet title action is another way of getting there, but probably just as difficult if not more so. This is , unfortunately, a common problem whan deaths occur and appropriate actions are not taken. While title can be cleared, it is time sonsuming and expensive to do so. Get your documents together and discuss the matter in detail with a capable trust and probate attorney.
Attorneys James and Christian are correct. Based on this unusual fact pattern, I would have to believe the property will have to be probated at some level. Nevertheless, an experienced probate attorney should be retained to determine just what needs to be done here. Good luck to you.
This information is presented as a public service. It should not be construed to be formal legal advice nor considered to be the formation of a lawyer/client relationship. I am licensed in Connecticut and New York and my answers are based upon the law in those jurisdictions. My answer to any specific question would likely be different if I were to review a client's file and have the opportunity to interview the client. Accordingly, I strongly urge you to retain an attorney in your jurisdiction with respect to any legal matter.
The other attorneys are correct. There are two potential alternative depending on the value of the interest in the property held by your aunt's grandmother. If 50,000 or less then you could you a special affidavit. If $150,000 or less you could use a short form Petition to claim the interest. Otherwise, probate will be necessary.
The general advice above does not constitute an attorney-client relationship: you haven't hired me or my firm or given me confidential information by posting on this public forum, and my answer on this public forum does not constitute attorney-client advice. IRS Circular 230 Disclosure: In order to comply with requirements imposed by the Internal Revenue Service, we inform you that any U.S. tax advice contained in this communication (including any attachments) is not intended to be used, and cannot be used, for the purpose of (i) avoiding penalties under the Internal Revenue Code or (ii) promoting, marketing, or recommending to another party any transaction or matter addressed herein.