Message in a Bottle-Invitation

So my almost 11 year old daughter wants a Fairy Party. I struggled for a little while wondering how I would accomplish this without making it seem like it was a 5 year old party.  Came up with a cute idea for the invitations. Similar to a message in a bottle.  Here is our invitation which I decided to sell in my shop:

We have come up with many other cute ideas for her party since. I will be sharing them soon :)