The Boy Who Was Never Loved - Troye Sivan AU

Troye grew up in a small home in Australia where he practically spent all of his time alone when he wasn't at school. When he was only a young teen, his parents left in the middle of the night and never came back. At first, Troye was relieved because he had been abused before, but that was until he realized that they were the only family he had.
Soon, he ended up living in a small orphanage, then a foster home. Everywhere he went, everyone knew about the silence. Troye didn't talk, and he hasn't for as long as he could remember.
Finally, his new sister, Sage, gives him the opportunity of a lifetime when she catches him singing in his room.
What will happen when his birth parents find out about his new career?