Final answer:
Joseph's brothers' attitude became more severe due to the cruelty Joseph experienced at the hands of his enslaver.
Step-by-step explanation:
The attitude of Joseph's brothers toward him became more severe as a result of the cruelty of his enslaver he related to them. When Joseph shared the details of the mistreatment he faced as a slave, it intensified his brothers' hostility towards him. This mistreatment included physical abuse, such as being thrown to the ground and stomped upon, as well as emotional and psychological torment.