What is the theme of this poem?

Your Perfect Little Girl

When she smiles,
The world stops,
When I smile,
It keeps moving.

When she cries,
You drop everything,
When I cry,
You fail to notice.

When she's in pain,
You give her anything,
When i'm in pain,
You don't even bat an eye.

She's your,
Perfect Little Girl.

I'm your,
Perfect Little Mistake.