Dr. Nick: Leave it to Gendo to badly socialize a child. If we're tracking Lilith's soul right, Rei I doesn't even have the "nuts because of split soul" excuse for her behavior like Kyoko does because at this point in time her soul should still be intact. The splitting presumably happened after her murder, once her soul had been sucked out of her corpse. The trauma of this murder is also presumably what triggers Unit-00's berserk incidents.
UrsusArctos: Given that Rei 1 is the Rei in the Eva, maybe her soul was split by this point after all? Maybe Gendo split Rei's soul ahead of time with the intention of making Rei 1 the pilot and Rei 2 the resident soul in the Eva, only for the murder to result in him switching the two around. I imagine a practical advantage in having two copies of Rei, each with a different half of soul : a body with the full soul of Lilith could be genuinely dangerous, and Rei 3 apparently has A.T. Field generation abilities to rival Kaworu's.
