At the end of the 80's/ beginning of the 90's, Garth and Lea had a newborn child Claire.
Before they could settle as a balanced nuclear family, as Garth would put it, Garth got into a car accident that cost the life of his wife on their way to pick up their daughter at his in-laws' house.
Garth lost the custody of his daughter and worked his way through reeducation to get it partially back 5 years later.
That's the year he got embraced.
That was his first contact with the world of the vampires that he deemed unnatural and evil.
His first thought as a vampire was to finish the job and kill himself for good.
That's what he tried to do, a few days after his funeral, by the cemetery. That evening, he caught the sound of a prayer. He heard his daughter talking to him for the first time by his grave (that was the first time he awakened his powers as a vampire). Ironically, he's never felt more connected to her than after his own official death.
From there on, his only goal was to indirectly support his daughter the best he could, at least until he'd heard from her that she turned out to be happy at some point in her life.
Every once in a while, throughout her entire life, Claire would pay tribute to her parents' grave, and Garth would listen from his apartment in the cemetery's vicinity.
She'd talk about her traumas, her depression and eventually about how she turned that around to help people deal with ailments of their own.
Years have passed and she's now working as a psychiatrist in the mental health department of Abbott Northwestern hospital, where Garth applied as a security guard with his alias Garth Field (name that he was forced to take).
The years he spent in the coterie made him realize how dangerous the vampire society actually is for humans. His first goal was to hold on until he could rest in peace, after witnessing his daughter's eventual happiness...
but his focus has become shielding her from that world, and making sure that she would never, ever, get caught up and killed in the crossfire.
Or worse... get embraced herself.
Garth holds a notebook with a list of vampires that can potentially present a real threat. He's considered what he would do after he fulfills his goal, which is letting Claire pass away peacefully of old age.
He doesn't intend to say goodbye to her. He has no intention of remaining a vampire for eternity. That day will become his opportunity to finally reunite with the family he never had the occasion to have.
Until then, he'll do everything to survive and protect Claire, including getting into the good side of his own coterie.
