here's one idea

and another

I think slightly brighter colored sheets would be pretty. But i wouldn't necessarily change out the duvet unless you had more of that color throughout the room. Coral or peach sheets, or maybe even a red print like what is in the artwork up on the wall would be pretty. If you wanted to have a brighter shade for the duvet too, I would incorporate that shade throughout the room in little pops of color. In a vase of flowers, the upholstery on a chair or cushioned stool, etc.

You have done an excellent job making this room serene. The nightstand and pillows even match the wall! I would leave the duvet as it is. I wonder if you might enjoy printed sheets with the blue color in the pattern, still maintaining the calm feeling in the room?

Ez, I don't think they are photos of her room.

Have you given any thought as to what sort of mood you want to create for your room. Blue and white creates a lovely serene mood for a bedroom but do you want to continue just with the blue and white or do you want to add further colours

An idea book on decorating with Wedgewood Blue

https://www.houzz.com/magazine/wedgwood-blue-returns-stsetivw-vs~1757958

Another room

[houzz=]

good catch olldroo - I thought the first photo was the actual room too! Blue & white are fine, I still like the idea of a peach or coral color pop though. Turquoise & coral have long been paired as jewelry - in victorian times this was very popular.

great idea about the coral. Thanks

A soft yellow, bordering on cream would be pretty too. Like the hydrangeas in a vase in the picture of a chair by a window.