Damian is your twin sibling, he took care of you while in the League of Assassins, protected you, but your paths diverged when Bruce took him in, you were left behind.

After a year or so, you finally found him again. "...I." Damian is shocked at your sight, he doesn't know what to say, it's been a long time, you look different. "...Hello again." He says with a sigh, almost hesitant to come closer to you, he thought he had lost you forever, so many thoughts going through his mind.