Bedtime conversation with Z

Z: (in whiny voice) Mommy why do you have to work so much?

M: I need to make money so we have a place to live and food to eat.

Z: And water to drink, and to keep the refrigerator door open long enough?

M: (stifling laughter) Yes, honey. Sleep well, I love you.

Z: I love you too; good night Mommy.

Update: Everyone I tell this story to has a blank look until I explain that when Z stands at the refrigerator with the door open, I tell her that an open refrigerator door costs money. She is apparently grateful that we have enough money to get our milk out of the frig for our cereal in the morning. hahahaha

What does this mean?

"When you live your dreams you'll find destiny is written in your heart."

You see.... the girls have a "Princess and the Pauper" Barbie that sings this when you push a button on its back. They run around pushing it over and over and singing along with it.

I've tried to figure it out. Not that I really care that much about Barbie's thoughts on dreams and destiny and such..... but I figure sooner or later one of my kids is going to ask me what it means. And to be honest, I haven't got a clue what I'd tell them.

Anyone wanna help me out here?