my father was a guarantor to one of his friends, now he has passed away and the one who took the loan's defaulting. and the bank's threatening us that they will recover the amounts from my mother's pension. can they do that? please help
No. If liability of your father as a guarantor was in his 'personal' capacity (i.e. without giving any property as collateral mortgage), no proceedings can be taken to recover any money from his pension or from your mother.