When you probate a will, do you have to notify the heirs?

Last Jan 07 my wife's father-in-law died. We have been waiting for the will to be probated. We just found out today that the step mother-in-law had already probated the will back in June without letting the children know. The county clerk told us that there was a lot of other paper work filed. A motion to dismiss, a motion to reinstate, and something about a lost will. We also found out that she was the executor of the will. Can you be an executor of a will that you will benefit from? And can you probate a will without notifying the heirs?