Legal Question in Real Estate Law in Illinois

Yes, unless there is something very unusual about this situation, your grandfather's estate goes to his children, but if any of those children already passed, the estate goes to the grandchildren. The rule is pretty simple, but sometimes there are weird exceptions, so you have to see a lawyer.

Good luck.

Assuming Illinois inheritance laws apply, yes, the descendants of a pre-deceased child would usually receive their parent's interest. This can be best reviewed in a telephone conversation so that all the facts can be flushed out.