Disclaimer: I do not own Itachi, Shisui and Sasuke, nor the storyline. I do own this little one.
Uchiha Itachi had always been a gentle soul, a pacifist among warmongers. A white raven among crows. He never raised his voice, he never glared nor sneered. Most of the time he had an unreadable expression on his face. Others, he had a small, melancholic smile tugging at his lips. There were however only three times Uchiha Itachi cried.
The first time, it was his cousin Shisui who saw the tears with his lone eye. The cristals drops on the young man's jaw were in his honour. For they both knew their time together was nearing the end. Uchiha Shisui, the forever smiling and down to earth man cried as well, red tears from the hollow where his lost eye used to be, clear ones from his unique remaining Sharingan, the only one Itachi truly loved to see. Because it was this man, this human, friend, soulmate who listened to his worries. Because it was this man who embraced him after another ANBU mission. Because it was this man who supported him in becoming a double agent.
Their tears mingled on the older one's face as he lay cradled in Itachi's arms, underneath an old willow. Shisui lifted his hand and softly stroked Itachi's face, murmuring sweet nothings to console the younger one about his own nearing death. His last words were an apology, a promise, a confession. It was a bittersweet goodbye as the soul of Uchiha Shisui left his body. His ghostly form kissed Itachi on his forehead and disappeared into the heavens, accompanied by the crystal tears of his friend.
The second time, no living eye saw the tears on his face. As he sat perched on a pole, overlooking the massacre he'd commited. These tears were out of mourning, as he remembered his mother sweet smile, his father's proud gaze, even as he took their lives. His soul was tainted, but his heart ached for his little brother, guilt overflowing his pain. No one noticed the tears falling down his face.
The last time Uchiha Itachi cried, his tears were not cristaline, but ruby red. He smiled despite the tears, as he made his way towards his brother. His brother, the unknowing, even foolish child, whom he only could love from afar. The one he'd given everything, his love, his protection, his mission. The tears were telling the world of his pain to place the burden on his brother's shoulders, of his sadness to leave the younger one behind. They spoke of his happiness to be reunited with his family, with Shisui, they spoke of his relief.
As he collapsed next to Sasuke, the last thing Uchiha Itachi saw, were the tears of his little brother, crying for his loss. The tears he never was able to cry for himself.