Step-Siblings, Half-Siblings, and Heirship
For determining heirship in Illinois, it's important to understand the difference between step-relations and half-relations.
A step-sibling isn't really a sibling or a blood relation at all. It's the child of two people, one of whom then marries one of your parents.
A half-sibling IS a sibling. It's a person who shares only one parent in common with you.
Here's an example:
John and Peggy Smith have 3 children (Able, Betty, and Cody) when they divorce. John remarries, to a woman named Margaret Jones. Margaret has one child of her own (David) from a previous marriage. Together, John and Margaret have two children: Emil and Fred.
If Able dies without a Will, who are his heirs? Under Illinois law, it's his parents (John and Peggy), as well as his siblings. And because, under Illinois law (755 ILCS 5/2-1(h)), "[i]n no case is there any distinction between the kindred of the whole and the half blood," Betty, Cody, Emil, and Fred are also heirs. David is not an heir.
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