Some types of grief are made public before the family is prepared. The two adult children of Mathilde Favier, Carlo and Héloïse Agostinelli, experienced their grief early on August 18, 2026, the day after their mother and her companion, film producer Nicolas Altmayer, perished in a traffic accident in the Deux-Sèvres region of France. The news spread quickly, as it always does when a well-known and beloved person passes away unexpectedly.
Mathilde Favier was fifty-seven. Directrice des relations publiques de Dior Couture, a woman who had dressed Michelle Yeoh, Charlize Theron, Jennifer Lawrence, and Anya Taylor-Joy, had spent decades establishing one of the most well-known careers in French fashion. In 2024, she released a book about Paris. She had attended the wedding of Nicolas Sarkozy and Carla Bruni as a witness. By all accounts, she led a full and public life. However, being a mother was the aspect of her life that she seemed to have guarded the most, and it also held the greatest significance for her.
The first person to speak was Carlo Agostinelli. In an English-language Instagram post, he referred to his mother as “the embodiment of life, the definition of joy.” It’s the kind of thing a son says when he’s attempting to condense a huge idea into a few words. He called her “our superhero,” thanked her for the values she had instilled in him, and then wrote, in a line that was almost too tender, “You don’t need to worry about us, Maman.” As you always looked out for all of us, we will look out for one another.” “Mamounette” was his childhood nickname when he signed off, and it instantly gave the entire situation a very intimate and genuine feel.
Before cofounding Nova, a San Francisco-based company that invests in young international talent, Carlo, who is roughly 26 years old, studied international relations at Stanford. It’s a path that resembles that of his father, Italian-American financier Robert Agostinelli, who cofounded Rhône Group and once collaborated with Lazard Frères in London in the 1980s, but it also feels very much like the aspirations of his own generation. Héloïse, his 28-year-old sister, chose a different path. She entered a world that her mother, perhaps more than anyone else, was familiar with as a model and has already made appearances for a number of brands.
Mathilde Favier married Robert Agostinelli, a man with ties to everything from Goldman Sachs to close friendships with Nicolas Sarkozy, and the couple had two children. Agostinelli married Dutch model Rosalie van Breemen in 2010 following their divorce, but that marriage also ended. With Nicolas Altmayer, Mathilde had discovered a new chapter in her life. On a departmental road close to Airvault, the two perished together when their car struck a large truck while passing another vehicle.
The way Carlo presented his farewell—not as the son of a fashion icon or as a bereaved public figure, but rather as a young child who had just lost his mother—has a subtle significance. “Héloïse is with me, and will always be.” Leaving each other behind, two people assure each other that everything will be alright.
Throughout her career, Mathilde Favier met some of the most influential figures in French society, fashion, and film. However, the tribute her son wrote out of grief rather than a press release may be the one that endures the longest. Simply put, it stated that she brought up people who know how to love one another. That’s a big deal. It may be the most crucial factor.
