Thank you both, I’m glad to see that I was almost correct!

You are right that it it a lyric from Antony and the Johnsons (a great band by the way).
To give some context, I’m writing a short story/long poem about a man that was abused as a child, and as a result hated himself and his body but didn’t know why. When he discovers the truth, he sees the sad, abused boy that he was as a child, but rather than being hateful of the way he looked, sees this past self with love and compassion.
The boy isn’t actually dead, but the person that he was is dead, if that makes sense.

I’m not sure if that’ll change the translation much!
I guess changing it to “oh, he was such a beautiful boy - o, был таким красивым мальчиком” might make more sense?