Known together as the Olsen Twins, Mary-Kate and Ashley Olsen are fraternal twins who are not only both actresses, but also work together as fashion designers and business managers.
The pair became famous when they were just 9 months old. That's when they began appearing as Michelle Tanner in 'Full House' -- a role they were cast in at only 6 months of age.
Nowadays, Mary-Kate and Ashley are among the richest twins in the world, partly thanks to Dualstar, their production company. These multi-talented actresses are fashionistas who have launched several fashion lines.
Read on for more of the most famous twins ever.
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