Yeah, although it's difficult to pinpoint when that started because a child's concept of death is so different. I was definitely suicidal in the adult sense by 14. One day it hit me how long I likely had left to live … just decades of years. Scores of years. It gave me this dizzying sense of horror, like some people might feel staring straight down a 200 ft. mine shaft.
I'd experienced that level of depression pretty continuously since I was eight, and intermittently before that. That was originally without the suicidal ideation though, because I just couldn't wrap my head around what death was. Up until age eight or so I thought that corpses were conscious, like living people. They just couldn't move for some reason. When a dead body got buried, the person "living" in it just lay there in their coffin, alone in the dark, forever. You can imagine why I wouldn't be in a hurry to enter such a state myself.
In case it's relevant: I was alternately neglected and abused at home, and bullied at school. I was actually the only kid I knew who had a chain lock on the inside of my bedroom door, as if I were an adult living in an efficiency apartment in some shit area of a city. Amazingly, my parents let me keep it.