@Stephie this helps much more with the "fit for a 10yo" part than the complexity but this character from mtg has been on a lot of cards so there's a lot of variations on her clothes, and a lot of people have cosplayed her so there's some ideas out there for actually possible things
Summery. Not too pale, not too dark. Festive, but not like one of the main guests or family. If I can, something with a hat or fascinator. Or use one of the ones I have and find a dress that goes with it.
http://www.schloss-solitude-gastronomie.de/ -> something that fits here. No ruffles.
I have again dabbled in fruit syrups and sodas from them. It started with an extraction of orange peels, (thanks @JourneymanGeek!) then a blood orange syrup from the leftovers of a blood orange drizzle cake (using up some of the leftover candied peels from before), now it was a cup of sea buckthorn juice and a grapefruit plus two lemons slightly past their prime.
In short, if it’s intense and leftover - there’s a good chance that I’ll boil it with some sugar and bottle it up.