No need. It depends on the style of violin music played by two children. According to the style of music, it can be an elegant simple black or white dress or a medieval court dress. Two girls should match. Dressed exactly the same. It's not very nice. They should be the same color or the same paragraph or have the same elements. So two children play the violin together, and their costumes don't need to be the same. Violin is widely spread all over the world and is the most important instrument in the string group of modern orchestras. It occupies a very important position in instrumental music, is the pillar of modern symphony orchestra, and is also a solo instrument with difficult playing skills. It is called the world's three major musical instruments together with piano and classical guitar.