Missing Sibling - Black Marble

I am writing for the info

I remember the time and the place

I can’t remember your face

Only for a moment

It’s easy to forget your place

I might be the last known survivor

In a diner they shot into space

I’ve painted every mountain

I’ve sketched out every choice

I can’t remember your voice

Only for a moment

And I just don’t even know why

I might be the last known survivor

On an island as big as the night