Will probate and closing of a will close the probate on the will of an earlier deceased?

Mother passed, willing her estate to surviving spouse. Will was probated but never closed. Spouse (father) passes. His will goes through probate and is closed. Now, property willed to the survivors is to be sold but the sale is being held up because mother's will was never closed. Wife/mother passed 1982. Will went through probate but was never closed. Husband/father passed 2005. Will went through probate, all t's crossed and i's dotted. Probate closed 12/2006. Wouldn't the subsequent probation and closing of the estate also close the initial probated will? The sale of property is being held up as closing attorney for the buyers insist that the 1982 will be closed. Stands to reason that it would have been closed with the closing of the deceased beneficiary's will. Are we being "fleeced" by the buyer's attorney? Why didn't the attorney handling our father's will, probate, etc. say something about the fact that our mother's will; passing on her half of the estate; half of what father passed on; was never properly closed? The wills and property in question fall under the jurisdiction of Georgia law.