Charlotte Casiraghi is getting ready to welcome Monaco’s newest royal!
The eldest granddaughter of Grace Kelly, who is expecting a child with fiancé Dimitri Rassam, was spotted out on a sunny day in Cap Ferret, France. The mom-to-be’s growing belly was on display in a chic one-piece bathing suit, which she wore with a matching wide-brimmed hat.
The couple have been staying close to Monaco on a Mediterranean cruise, spotted in St. Tropez as well as sailing to the Italian island of Pantelleria, where Rassam’s mother, glamorous French actress and former Bond girl Carole Bouquet, has a vineyard.
A source previously told PEOPLE that Charlotte is “due late this summer, early September,” and friends suggest that the couple will marry in the spring.
After weeks of press speculation, the 32-year-old unveiled her bump during the Monte Carlo International Horse Jumping events in July. The news comes a few months after Princess Caroline of Monaco’s eldest daughter confirmed her engagement to Rassam by wearing a diamond ring on her left hand as they attended their first official Monaco event together in March.
The child will be the seventh grandchild for Princess Caroline (the 62-year-old royal’s clan has welcomed two additions since April) and the second grandchild for Dimitri’s mother.
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Charlotte, who is ninth in line to Monaco’s throne, and the 36-year-old film producer (his credits include Netflix’s The Little Prince) quietly began seeing each other in Dec. 2016 after being introduced by friends over dinner. They got engaged in March while on ski vacation in Zurs, Austria, with Princess Caroline.
The couple are graduates of the Sorbonne University in Paris, and each have children from previous relationships: Charlotte has a 4-year old son, Raphael, with comedian Gad Elmaleh, and Dimitri has a daughter from his marriage to model Masha Novoselova.