The 13th Mother's Day

This is the 13th Mother's Day that has come around since your life came to an end.
When you passed away, I didn't just lose a mother, I also lost my best friend.
We used to spend Mother's Days together but we can't anymore.
You went to Heaven twelve years ago when you were sixty-four.
You became a mother in 1967 when you brought my brother into the world.
I was born almost four years later and you incorrectly believed I'd be a girl.
An aneurysm ended your life and we buried you in the ground.
I can not enjoy Mother's Day because you're no longer around.
I'll join you in Heaven but I don't know when.
But it will be great when we're together again.