Treasure Island is an adventure tale, but it is also the story of one boy’s coming of age. At first, Jim is a timid child, but by the end he has matured incredibly. In other word, it’s about the brave of child whose name is Jim Hawkins in the story.
Ex. He has outwitted pirates, taken over a ship, and saved innumerable lives.
So, Jim has become an adult in character if not in age.
The courage is good. Although you have to defeat the problem how many times, you will be able to get through it. Likes the quotes is "Our greatest glory is not is never falling, but in rising every time we fall".