Why is it hard for Phillip to tell. His parents about timothy and the cay?

Phillip is hesitant to tell his parents about Timothy and The Cay because he is afraid they won't understand or accept his friendship with a black man like Timothy. He is also unsure how they will react to him being stranded on an island with Timothy, and fears their disapproval or prejudice. Additionally, Phillip may feel guilty for relying on Timothy and not wanting to admit his own vulnerabilities to his parents.