Sentence:  They are also very sympathetic, especially Caesar's orangutan advisor, Maurice (Karin Konoval), who takes a shine to a human <WSD>moppet</WSD> (Amiah Miller) he finds hiding in the back of a shack, and the poignant Bad Ape (a scene-stealing Steve Zahn), a mangy chimp who was beaten so often in his zoo-animal days that he came to believe what his handlers were shouting was supposed to be his name. 
Meaning of the word marked with <WSD> tags:  A child. Often used lovingly or in an affectionate way.