Define Normal

This is an old one that I found. I wrote it based on a book I read called "Define Normal"

From day to day
I live this secret life
No one understands
What this is like
I've got 2 little brothers
Who are depending on me
I'm startin to expect
They might call me "mommy"
But where is the one
Whose job I have against my will?
She lies in bed all day
Saying that she's ill
But then she comes around
And when she's got her fill
She leaves things up to me again
To use my money for bills
So, good-bye college
My money's all been spent
I've only got enough
To pay the next month's rent
I want to run away
And I know I could
If it weren't for my little brothers
I most definitely would
So next time to say
That I'm normal
I'm going to say:
"Define Normal."