To Kill A MockingBird character Analysis

In the book To Kill A MockingBird the character Jem shows to be a interesting character with a big imagination. Questions I had for the character Jem was, towards the end of the chapter why does Jem not want Scout to act like a girl? Is he afraid of losing his sister? I also wondered why Jem feels the need to prove his fearlessness to Scout all the time. From the book so far Scout seems to think that Jem is a fearless and already thinks highly of him. Jem is the Oldest sibling in the Finch's family and I am the oldest in my family. Like Jem, I feel as though I have to be fearless in front of my siblings since I am older and should be more responsible and brave than they are. The perception of being fearless give one's siblings reinsurance in a situation as well as  the feeling of safety which is important in a situation that requires everyone to stay calm. Fear is usually associated with being seen as weak and since one wants their siblings to look up to them they feel the need to be fearless and confident. Also like Jem I feel as though I have to be a role model for my siblings. Jem tries to act as though he knows what he is doing all the time and is pretending to be confident to hide his fear. I try to do what is expected of me by my family to set an example for them in what is right and what is wrong. Jem's strengths thus far in the book is he cares about his sister and looks out for her. However his weakness is he believes in everything he is told. I predict that his belief in everything he hears from others will hurt him emotionally later on in the book.