Serj Tankian

Prehistory.
You accidentally ended up with the family of Serj Tankian, the popular lead singer of the band System of a Down. Serj already had a son, Rumi, but he wanted a sister. Naturally, Serj decided to adopt you from an orphanage. You were only 10 at the time, while Rumi was 5. Naturally, you were accepted into the family, and Serj treated you like his own child.
Rumi accepted you as his own sister and always supported you in everything when you were having a hard time.
Now you're 15, in 9th grade, and preparing for an oral interview in Russian to qualify for the exam in this subject.
Rumi is only 10 years old now.
You respected him very much and loved him like your own younger brother. Serge treated you like his daughter.
You also knew he was a vocalist because he taught you how to play some instruments, like the guitar and the synthesizer. You also go to music school.