The will would control dispositions of property owned solely by your father at death, whether a small estate or not or under a small estate procedure. IL attorney would be able to advise you as to the small estate thresholds, etc. I imagine the only issue would be if the predeceased daughter left issue (children) and if the will stipulates that her share goes to her children or if the share goes to the other beneficiaries. Most wills state if a gift is "per stirpes" and in the absence of that language typically a gift "lapses" (becomes ineffective) and goes to remaining beneficiaries.
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Unfortunately your information does not help us help you, because we would need to see the actual will and the language it used. For example, if the daughter had children of her own and the will talked about property distribution "per stirpes" (which they often do) then those children would be entitled to receive their deceased mother's share. If not then her legacy may very will be gone. There are procedures for small estates, you will need some kind of probate for the home if it was in your father's name, and buyers of the cars will want to see court authority too.
The terms of your father's Last Will and Testament will be interpreted by the Court to determine whether the deceased daughter's share goes to her lineal descendants or whether it lapses. If the language in your father's Last Will indicates that the bequest is "per stirpes" then it will go to the daughter’s descendants. A small estate affidavit is frequently used to distribute a smaller estate however it cannot be used with real property. It is possible to sell the real property and have a title insurance company insure over the transfer using a "Bond in Lieu of Probate". The Title Company will charge a fee based upon the value of the property and the time elapsed since your father's death, however it will only agree to the Bond in Lieu if all the beneficiaries under the Last Will and any heirs who might have a right to challenge the Will must be signors on the deed transferring the property and must indemnify the Title Company in regard to potential claims. The problem you have with a Deed in Lieu is that there would have to be an agreement in regard to the deceased daughter, and more than likely regardless of what the Last Will says the descendants of the deceased daughter would have to sign the Deed as potential heirs. Obviously if your family were to decide not to give a share to the deceased daughter’s family they clearly would not agree to sign the Deed. So there is a strong likelihood that you will have to probate your father's Last Will. You need to retain an experienced Probate or Elder Law Attorney to review the Last Will and the facts to properly advise your family. Good luck.
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