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My name is ***** ***** am happy to assist you with your enquiry.
I'm afraid that it was only inn July 2008, when the Transferable allowance was introduced whereby any unused part of the nil rate band on the first death could be transferred and added to the nil rate band of the second to die.
As your Father died in 1991, no unused allowance could have been transferred to your Mother's Estate.
I am sorry this is not the answer you were looking for, but it sets out the legal position.
Many thanks Aston for your help, if it had been different then the Probate office may have had some explaining to do !!
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