First of all,Jem shows his inner self by showing his sister Jean louise good manners. To prove this, “Now I mean it,scout,you antagonized aunty and I’ll I’ll spank you”. This shows Jem has matured a lot because he behaves as a parent/adult now. As scout misbehaving,Jem orders her to stop or he’ll spank her as an adult would do. To end with Jem evolved by showing his responsibility of growing into the adulthood.
Secondly, Jem evolved by being harmless