Dmitri and his twin brother Andrei were born to an Outlander and a woman from the Dome. Their affair was rather illicit and the woman's family, after discovering she was expecting a child, demanded she marry, and preferably someone acceptable, none of these wild ideas of marrying an Outlander. Svetlana had intended to run to the Outlands and make a life with Daren out there, but her family pushed through an arranged marriage quicker than she could leave.
The boys were thus raised by someone who was not their father, a man named Eric Von Einzbern, if you could call that being raised. Mostly, Svetlana took the brunt of the man's abuse, but the boys weren't unaware of what was going on, either. Incidentally, one day, Eric hit slammed Svetlana into the counter a little too hard and killed her. He had no intention of getting saddled with her bastard children, and rather unceremoniously handed them off to the Special Other Forces, which wasted no time in splicing the both with an Other, making them part-bloods.
As it happens, both were also Losrian; and it showed when they had not only their own powers, but those of the Other they were spliced with, too. The lab technicians say Dmitri and Andrei are a special kind of part-blood, spliced with a unique sort of Other, but what that means, neither has ever figured out. The only thing they know is they're consistently different than the Republic expects, capable of things they aren't supposed to be able to do, and tend to be extremely defiant. Or did, at one point.
Dmitri raised hell after nobody would reunite him with his brother, going so far as to shadow beam the crap out of the laboratories in retaliation until sedated, but this made the Republic think Dmitri would eventually harm his twin, and continue to refuse to see reason and unite them. Only Gabrielle, a psychologist working for the Medical department, suggested otherwise, and she managed to earn Dmitri's trust. He still has the potted flower she gave him to encourage him to care about something besides himself and Andrei.
She 'took too long,' and was reassigned. Dmitri eventually became depressed and withdrew. Finally, Jadyka Maitra, quite the name in the Special Other Forces, decided to go around behind everyone's back and assign both twins to him and reunite them before anyone could argue. They're now quite happily doing whatever it is Jadyka wants them to, without giving him too much argument about it, though he takes what little argument he gets in stride. They're supposed to be going to Pyxis, but there's a new handler Jadyka's mentoring that they're waiting for.
In the interim, Jadyka's helping the twins learn to control their newly discovered telepathic abilities, and strengthen them, as well as teaching them gardening for fun.