Legal Question in Wills and Trusts in Illinois

In some circumstances they would. For example, if they were named in the will, or if there are no children or spouse.

Presuming the decedent was married on the date of the decedent's death, with or without surviving children, siblings don't have too much in the way of rights. However, if the deceased person was not married and left no living descendants on the date of death, the most important right of the sibling of a deceased person would be a right to notice of the existence of the decedent's will and notice of the pendency of any probate proceedings.