If you wish, you can keep his bedding the same for a while, to give him the comforting feeling of some sort of continuity in the transition. Or you can have brand new custom bedding designed to match the theme of his big boy bed. Which option is best depends really on the child.
Then with that same color theme, you can then select the rest of the items that make a bed complete, namely: bedding, including pillows, sheets (that's both fitted sheets and top sheets), blankets, comforters, and bed skirts. Better yet, have the same children's furniture designers that help you create your little princess's custom theme bed design all her custom bedding as well.
Some parents and kids might want to discover new trends in bedroom designs. One effective way to create a "new look" is by using a bright color for most part of the room. The walls can be painted red, for example. The accessories can be carefully chosen to match the color red. Some people might opt to include only white accessories into the room to create that effective contrasting result.
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