Interesting Conversation with Katherine

Yesterday I had an interesting conversation with my 7 yr. old.

Katherine: Mom don't throw out the empty Dr. Pepper bottle in the refrigerator.

Mom: Why?

Katherine: It's got my voice in it... ya wanna hear?

Mom: No! Don't let your voice escape. How'd your voice get in the bottle?? Ursula and
Ariel???

Katherine: Yup! Just like the little mermaid.

My question is.. why do we need to store her voice in the refrigerator??? I'm all for preserving her sweet little girl voice. I know when she's 16 I'll be longing for it.