This Tree

This tree’s green leaves
Ruffle in the wind as if they breathe.
This tree is my storybook.
It’s easy to read if you really look.

Do you see that roughly carved heart?
It was done by two lovers before they part.
It was by an announcement nailed to this tree she learned,
He joined the army and never returned.

Do you see that mangled straw hat caught up high?
It got stuck when a happy man tossed his hat to the sky.
It’s been there for a while and it’s frayed,
But in the tree the old hat has stayed.

Do you see that knotted root poking out of the dirt?
My grandpa used to always trip on that and get hurt.
He still walked to this tree everyday with a cane;
He did so until he could not longer walk upon this lane.

Do you see that stump where a branch used to be?
It was how father fell out of this tree.
He’d been trying to pick a blossom for another;
She was the woman who became my mother.

This tree finally fell,
But it still had a story to tell.
It is of my baby brother’s first and last days;
Of when he was still learning his ways.

To others this story is lost,
But I remember the little boy whose life this fallen tree cost.
I remember how this tree crushed his every limb;
This fallen tree reminds me of him.

- - -

Well, this was supposed to be...well, not a happy poem, but a neutral sort of thing. Of course, I completely screwed it up so it's kinda sad now.
I need practice writing happy poems.
Reviews please?