Tween Bedroom Ideas

[Aginplease]

Ive posted about this paper before, but cant find my post.
DD is moving bedrooms, she has choosen this wallpaper, which has a grey background, with pinks and greens on.
She has decided that she wants very light green walls, to match the green on the wallpaper. The carpet is grey and wont be changed.
So do i go for very light pink curtains or grey? She is 9, so trying to choose a look that will last a few years.
Her furniture is white, and her bed is a plum colour, which im not changing as its not that old.
How can i bring all these colours together?