My 6 year old client gave very clear direction in that she wanted a purple room. Her mother had reservations but I assured her that I could make purple work. It can be a tough color to work with but the key in this case was to temper it with lots of white.
As I often do with bedrooms, I started with the bedding because it’s much easier to work your color scheme around bedding than it is to find bedding that works within an established color scheme. And though butterflies are predominant in the room, I still prefer to refer to the project as, “Purple Princess” since purple was a requirement, and it was designed for a little princess :-).