What does “per stirpes” mean?

In a Last Will, what does "per stirpes" mean?

             We get that question a lot, as “per stirpes” (pronounced “purr STIR pees”) is a very useful Latin expression for Last Wills.  Someone somewhere a long, long time ago started using it as a shortcut expression, and it stuck. 

             We’ll skip the Latin lesson.  Over-simplified, it means “passing down to the heirs of the beneficiary if the beneficiary dies before you.”  In a practical sense, for many people it means in their Last Will that if your child predeceases you, but leaves children of his/her own, those children (your grandchildren) stand in their deceased parent’s shoes and inherit what the parent would have inherited.

              So now you know what “per stirpes” means.