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KD
Since: May, 2009

Ummmmmmmm is there any specific trope were the main character group gets a new addition?
I have no idea how to explain this, so, here's some examples:
Wow! Wow! Wubbzy!:Daizy (idk how to write her name) debuted in season 2, and is in the main cast.
The Lion Guard:Anga turns into a main character and part of the Lion Guard in season 3
Edited by MaferYet