Mary-Kate & Ashley Olsen: The Row, Elizabeth and James and Olsenboye

Mary-Kate Olsen and Ashley Olsen became the co-presidents of the Dualstar company on their 18th birthday in 2004, becoming the eleventh richest women in entertainment in the world, according to Forbes. The twins design for, own and manage three colthing lines: Olsenboye for JCPenny, ready-to-wear Elizabeth and James and a high-end line, The Row.

Image courtesy of Larry Busacca/WireImage