Yes I quite understand you want to know who her parents are,with comfirmation,and if it was there and I could find it, I would have given you the details,brick walls we all have, and so you have to keep chipping away,there are no further records relating to Mary and James at this church after their marriage on Lancashire opc,so have you looked to see if they have other children in another parish that may help you to link them back to your ancestors,
Mary Hadfield and James did indeed marry 1739 Ashton under Lyne
but it doesnt mean your Mary who has her children baptised Ashton in Makerfield,two totaly different places,is the same person you are looking for, they may have been related,keep looking,
