Board Thread:Episode Discussions/@comment-1181222-20170830100203/@comment-5085906-20170904095922

@Thekillman

True, there are some holes with the whole Sharingan and Mangekyo awakenings, but saying that you need to lose a dream associated with the person who dies and that person has to be THE CLOSEST person at that time requires a huge leap in logic. If we take novels into account, Itachi casually walked to a battlefield littered with corpses, some of them Uchiha, and that was not enough to awaken his Sharingan. In the meanwhile, Sarada gets excited at the prospect of meeting Sasuke and awakens hers. If anything, that mainly points out to the Sharingan awakenings being related to the individual Uchiha's disposition.

And just because Itachi was friends with Shisui and was with him for most of the time does not mean he was the closest to him. By that logic, we could argue he was close with Kakashi too, seeing as how they were both in the ANBU. Itachi discarded his feelings to kill his parents and, in the novel, a girl that was infatuated with him and that he, if not loved back, at least cared about but drew a line when it came to Sasuke. Even Tobi himself deduced that Itachi's love for Sasuke overshadowed Itachi's love for his clan.

Now, granted, I am delving into deep headcanon territory myself, but that's only because we haven't gotten an intricate look on the mechanics of the Sharingan yet, in spite of being the most developed dojutsu so far. The fact that only Izuna and Madara managed to awaken the Mangekyo during the Warring States, a period of constant strife and death, could just imply that the Uchiha were desensitized to violence and did not care about their blood relatives whereas that wasn't the case with Madara and Izuna.