Chris McCandless is the main character of the book Into the Wild by John Krakauer.
In this book, we learn that McCandless is the product of his father's second marriage. However, McCandless also learns that his father had not yet divorced his first wife when McCandless and his sister were born. Therefore, the father led a double life. This realization profoundly affected McCandless. This knowledge made him felt betrayed and angry. To some extent, this sense of betrayal and anger explains why the choices in life of McCandless are so different from the choices his parents wanted him to make.