In Illinois, an estate is passed on to the heirs through a last will and testament or through the rules of intestate succession when no valid will is in existence at the time of death.
In Illinois, if the decedent made a valid will, then the estate will be divided per the instructions in the will. To be valid, a will must be in writing, signed by the testator and witnessed by two witnesses who are not beneficiaries. The testator must be at least 18 years old and of sound mind.
The spouse and descendants inherit equally. Next in line to inherit are the parents, siblings and descendants of siblings. If the estate is not exhausted, then grandparents or descendants of grandparents are next, followed by great-grandparents and descendants of great-grandparents. Last in line are nearest kindred who do not fall into one of the other categories.
No Heirs or Remainder
If there are no heirs of the decedent, or if there is a remainder after all heirs have inherited, then the real property of the estate (or portion thereof) is passed to the county where any real property is located. The rest of the estate passes to the county where the decedent lived.