her brother Caleb (Ansel Elgort) has fully defected to Erudite and fights back against her, forcing Tris to undergo a series of trials at Jeanine's command to prove that she's truly divergent.

Tris isn't the sole confirmed Divergent ... council members of Abnegation and Four’s father, is also a Divergent, and Tori’s brother, George, was also one, hence why she knew the dangers ...