So sad poem
But I love it
Coming from the heart
Well wrtten

That question, what, if and when
it is unfortunate that you have lost
both grandparents to cancer, not given
the opportunity to meet them

Very heartbreaking. a touching poem dedicated to them. 5/5

This made me think of my grandfather.. My dad used to tell me stories about him, and this made me feel that same sad feeling when you think of 'what could have been'.
This is a really powerful write for you let the reader connect; even though they haven't really experienced this, the emotion you had within and throughout this piece is so strong.
I'm truly sorry for your loss, and I do know how you feel.
Critically commenting: the capitalisation did not work. I advice you to not capitalize the first letters unless it is necessary, because it is distracting and ruins the overall flow for some readers who take into account every detail (:
The lack of punctuation seemed unintentional, but it worked to a degree so it's up to you if you want to keep or change that.
The title really drew me in. It was interesting; my first thought was that the persona would want to be with his lost loved one, hence a two-person grave. But I like your idea as well. Great job.
Keep writing
-X

What could have been... sometimes its good to just ask that and let our imagination run, other times its good to have some memories. Its a sad piece. I'm not sure what to say. it brings some memories back.