I'm assuming this is for your daughter(s)' room, if so have you asked them what color they would like. Could make it a lot more fun to decorate if you collaborated with your girl(s). Lavender/pale purple seems to be a popular choice. (I don't have any specific color in mind--I just go to the local BM store and narrow it down from the selection and try out a couple of samples on my walls) And remember you can always bring in color through art, decals, etc. if you decide to go more neutral (I wouldn't--after all a girls' room should be fun, not safe). Here are some possibilities:

what about light aqua/turquoise?

How about a lighter shade of green that you can see on the frog sitting on your daughters' night stand? A green-yellow is a natural complementary color to the colors of your existing bedding: purple and pink (on the opposite side of the color wheel) Together, they are actually considered the most beautiful complementary colors. You could also add some accents (pillows, window treatment, etc) in a darker shade of green. Your white furniture will also benefit from the darker walls (contrast).

I vote for a light apple green as suggested above.

Ask the girls first. They might surprise you!
I think a pale green without as much yellow as an apple green would be pretty. Green is the opposite of pink on the color wheel.
Aqua is a color that is between pink and purple on the color wheel. It could work, as well, as previously suggested.

Thank you everyone! This was my first post and I received great feedback from all of you. Much appreciated!

Will you post an " after" photo for us?

Asked my daughter and she wants blue! I'll post a pic once complete!

I am looking forward to seeing the completed room!