I am trying to find an anime I have watched a long time ago and want to watch again but can't remember the name of.

This anime is about a common (i think 7-10) little girl who lives in a common village. And in her country there is a handsome prince that every girl is in love with. She also wants to be with the prince too (obviously). But she knows she is too small to be with the prince. Then one night she sneaks in the castle when there is a party. There she meets somebody (i think) and gives her the power to become older. Then afterwards in the castle she meets the prince.
I can't remember anything after that.
Please help me find this anime! I would really appreciate it!
P.S. Some information may be wrong in a few places. Sorry it really was a long time ago! Also please insert an image if you can please! Thank you