Monaco royal Beatrice Borromeo supported by sister-in-law Tatiana Santo Domingo during poignant event

It was a family affair for the Monegasque royals on Tuesday, with sisters-in-law Beatrice Borromeo and Tatiana Santo Domingo attending the Christian Dior show during Paris Fashion Week.

Tatiana and Beatrice are sisters-in-law through marriage, with both wedded to members of the Casiraghi family of Monaco. The ladies have a lot in common, including a love of fashion, with the duo sitting front row for the Christian Dior show.

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As stylish as you'd expect for such a soiree, Tatiana wore a long, brown suede coat, paired with a white shirt and black shoes and trousers. Beatrice,

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Though they looked ultra-glamorous at the fashionable event, it was likely an emotional and poignant event for Beatrice, who was close friends with the brand's longstanding PR director, Mathilde Favier, who sadly died in a car crash in August, alongside her partner, film producer Nicolas Altmayer.

At the time, Beatrice took to Instagram to share her heartbreak, writing: "When I think of you, so much warmth comes my way. Your smile, which always made me feel so at ease. Your stories, your wit, and that spirit of a little child within the most elegant, balanced woman.

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"I will miss you deeply, Mathilde. Your hugs, your laughter, your light."

Referring to the children of Mathilde, Beatrice continued: "My heart is broken for Héloïse, Carlo, Victoire, and for your whole family - made of all the people who felt loved and supported by you. You and Nicolas live on in our hearts."

Putting on a brave face

Despite the tragic loss, Beatrice has been putting on a brave face, attending several Fashion Week events, including Vogue World in Milan, for which she wore a beautiful silk shirt and skirt combination, looking statuesque and otherworldly.

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She was also quick to congratulate her younger sister-in-law, Alexandra De Hanovre 27, who got engaged in mid-September, meaning Beatrice and Tatiana are set to gain a new brother-in-law, Ben-Sylvester Strautmann.

The two have been dating for around 10 years, and Alexandra announced the happy news on Instagram, with congratulations flooding in from royals and aristocrats around the world. Beatrice wrote: "I'm sooooo happy for you guys!!!!" while Princess Olympia of Greece added: "Omgggg congratulations!!!"

We are expecting quite the turnout of royals when their big day comes around…