Their step-mother, however, had always been most generous to them; indeed, they were so young at the time of their father's remarriage that they always thought of her as their own mother. 
They hated their step mother. 
mnli hypothesis: They hated their step mother.  premise: Their step-mother, however, had always been most generous to them; indeed, they were so young at the time of their father's remarriage that they always thought of her as their own mother. 