Why does Gene's fear disappear at the end of the chapter- Chapter 4

Throughout the story Gene would constantly look up to Phineas because of his incredible athletic ability. He always assumed that Phineas was the one that continued to impress and amaze people until Gene discovered that he possessed talent in academics. In the passage , Gene and Phineas both climbed the "tree," and Phineas fell down preforming an awkward landing. This action destroyed Gene's fear because he learned that Phineas was capable of doing poorly in his strengths as well. "With unthinking sureness I moved out on the limb and jumped into the river, every trace of my fear of this forgotten."(p. 60)

Prior to this event Gene had reached the conclusion that Phineas was sabotaging his success in academics by distracting him with athletics. While they were both on top of the "tree" Gene displayed a side to him that we have never seen: he fought back. He shook the limb which caused Phineas to lose his balance and fall down. This act showed Gene that he was also capable of sabotage thus destroying his fear of Phineas's power against him. This deed foreshadows the upcoming events because his action made him become a stronger individual. Gene is now able to stand up for himself therefore Phineas can't have power over him any longer. What conflicts between Gene and Phineas do you think were destroyed and/or will come after this event?