inheritance for minors

What is the name of your state? Georgia

In October my son's father died without a will. His estate is still in probate. Six months later the father's paternal grandmother died, my son's great grandmother. My question is about what I have read about "stepping up". Children taking the place of their parents in the will. If probate is still open does that mean if there is an inheritance for the deceased father will it go into his probate?

Thanks,

Probate being open on the father means nothing to the probate/distribution of the great grandfather. At the time of great granddad's death, the father is just as dead as he would have been if the father's probate had been closed.

The question is what greatgrandad's will (if any says) or the laws of intestate succession are for the surviving heirs.

I guess my question(s) is/are:

an inheritance would not be considered a creditor during probate?
If there is an inheritance in the will and he has died what happens if nothing is specified in the will?