My daughter died four years ago with no will, so her estate is being probated using the State of Illinois will.

The facts you have described need to be developed in a face to face conversation with an attorney. This does not sound like something on which you can go it on your own. You may only need a better explanation of the paperwork you received.

I assume you are stating that there was not a will and that the estate is being distributed under intestacy, meaning half of the probate estate to the spouse and half to the child (if there is anything available for distribution). If instead, you are referring to a will that your daughter had prepared in the State of Illinois, then the terms of the will need to be known.

If the estate cannot cover the decedent's bills, the heirs should not be personally responsible for the debts. With rare exception involving some wrongdoing, the heirs should not be putting their own money into the estate.

Is your grandson being asked to pay or is he receiving notification of something that will be paid from the estate? Has he previously received distributions that should have been used to pay obligations of the estate? Did your daughter give him money before she died that can be considered as having been done to avoid creditors?

There are numerous questions. Try to sit down with an attorney. Perhaps find someone who offers a free or low-cost initial consultation. Make sure to bring a complete file of documents. If you do not have everything, get copies at the courthouse before meeting the attorney.