Marta Ortega Perez has a current net worth of $1.5bn. That is more money than most of us will ever see in our entire lives, but it actually seems like quite a small share of her family's fortune. She's the daughter of Amancio Ortega who was, for a long time, the world's richest man. He's still not doing badly; he's now worth $73bn. Considering the vast sums that less-wealthy fathers have given to their daughters, only giving his daughter less than a seventieth of his cash seems miserly!
The Perez money mostly comes from fashion and clothing, with Zara being the pick of their numerous brands. Nobody knows whether Ms. Perez is involved in the company or not - the Ortega family are notoriously private - but it is known that she went to London's European Business School, so it seems reasonable to assume she's putting that learning to good use.