Charlotte Casiraghi and her fiancé Dimitri Rassam are expecting a baby.
After weeks of press speculation, Casiraghi, 31, unveiled her bump during the recent Monte Carlo International Horse Jumping events. 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.
A source tells PEOPLE that Casiraghi is “due late this summer, early September.”
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, glamorous French actress and former Bond girl (For Your Eyes Only) Carole Bouquet.
Casiraghi and Rassam got engaged in March while on ski vacation in Zurs, Austria, with Princess Caroline. Their wedding plans remain secretive. Initially, it was speculated that they might marry as early as this month.
The eldest granddaughter of Grace Kelly and the film producer, who have been inseparable since, split their time between L.A., Paris and Monaco. Both 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.
This article originally appeared on PEOPLE