Francoise Bettencourt Meyers, the world’s richest woman, is bolstering her family’s investment company with a hire from McKinsey & Co. amid a surge in the value of L’Oreal SA, the cosmetics giant founded by her grandfather.

The heiress’s Tethys Invest SAS named Cyrielle Villepelet as managing director to work alongside chief executive officer Alexandre Benais, according to a statement. Villepelet was most recently a partner in the Paris office of consultant McKinsey, working in the luxury, fashion and consumer goods industries.

Tethys invests in areas that don’t compete with L’Oreal. Last year, it bought into decade-old retailer Sezane alongside private equity firm General Atlantic, and in 2017 invested in French private hospital operator Elsan. The firm is partly funded by L’Oreal dividends.

Bettencourt Meyers, 69, is the biggest single shareholder in L’Oreal with a near 35 percent stake. She’s one of a clutch of French luxury titans whose companies have benefited from demand for high-end makeup, clothes and jewelry. The ultra-wealthy group also includes Bernard Arnault, the world’s richest person and founder of fashion empire LVMH, and rival Francois Pinault, who started Kering SA, owner of brands like Gucci and Balenciaga. The Wertheimer brothers, who own Chanel, and the family behind leather goods maker Hermes International are also in the clique.  

Arnault is worth $188.3 billion, according to the Bloomberg Billionaires Index, while Bettencourt Meyers is No. 12 in the ranking with an estimated $81.1 billion. The Wertheimer siblings are 24th and 25th with €48.3 billion each, and Pinault ranks 30th with $41.4 billion.

As a leader in the global skincare market, L’Oreal could benefit from higher-than-expected demand for beauty products should China rebound this year, UBS analysts including Guillaume Delmas wrote in a note. The shares have more than doubled in the past five years, valuing L’Oreal at €205 billion ($217 billion).

With a reclusive reputation, Bettencourt Meyers is on the board of L’Oreal along with her two sons, Jean-Victor Meyers and Nicolas Meyers. She has written two books — a five-volume study of the Bible and a genealogy of the Greek gods — and is known for playing piano for hours every day. She came into her fortune following the death in 2017 of her mother, Liliane Bettencourt

In Greek mythology, Tethys was the goddess of fresh water and the mother of rivers and springs. 

Villepelet is set to start at the investment firm next month.