I don't know what country you are in or what system your daughter competes under, but keep in mind that there are some fairly restrictive dress codes for children in dancesport. If you are in the US and your child is competing in USA Dance sanctioned events, you can look at the dress code by going to
http://documents.usabda.org/1341/2881/2006_2007_Dress_Code_12_06_05.pdf
Since she is eight years old, section 1.1.2.1.2 would apply to her.