Why is Timothy's death important (what does it teach Phillip) in The Cay by Theodore Taylor?

In The Cay by Theodore Taylor, Timothy's death is important for a couple of reasons. First of all, Phillip quickly realizes how much Timothy has taught him in the amount of time they have been on the cay. Phillip started out resenting Timothy and thinking he was less important than Phillip and his white family and friends, but during their time together, Phillip begins to understand that Timothy is very intelligent about the ways of the outdoors and that he is just as important as anyone else. When Timothy dies, Phillip recognizes that Timothy has been a father figure to him and he loves him like a father.

Furthermore, Phillip now has all of the qualities he needs to survive alone on the cay, thanks to Timothy. Once Timothy is gone, and Phillip has to do everything for himself, he sees what an important teacher and influence Timothy has been for him. Even after he's finally rescued, Phillip prefers spending time down on the docks with those who knew Timothy--he has matured way beyond the little boy he was when they were first stranded.