She welcomed her first child, daughter Wilde, in May last year.
And Lady Mary Charteris offered a glimpse of her impressive abs in a revealing orange bikini as she joined a slew of stars for Cara Delevingne's 30th birthday celebrations aboard a lavish yacht in Formentera.
The socialite, 35, wowed in the colourful two-piece with a pale pink floral trim as she enjoyed Cara's wild party in the Spanish sunshine.
Sensational: Lady Mary Charteris, 35, offered a glimpse of her impressive abs in an orange bikini at Cara Delevingne's 30th birthday celebrations aboard a lavish yacht in Formentera
Mary, the daughter of James Charteris, Earl of Wemyss and Catherine Ingrid Guinness, of the Guinness dynasty, slipped into the orange bikini top with black denim shorts as she headed up the yacht's deck.
The DJ, who is a longtime pal of Cara's, covered up with a matching black waistcoat which hung open to display her bikini top.
With her phone in hand, Mary appeared to be enjoying the sunshine during her friend's birthday celebrations as she joined a slew of stars including Sienna Miller and Margot Robbie at the event.
Hard to miss! The socialite wowed in the colourful two-piece with a pale pink floral trim as she enjoyed Cara's wild party in the Spanish sunshine
Relaxed: The DJ, who is a longtime pal of Cara's, covered up with a matching black waistcoat which hung open to display her bikini top
Lady Mary is married to Jessie Furze, star of electronic rock group The Big Pink.
She was pictured with a blossoming baby bump on numerous outings before welcoming her first child, Wild Jessie Furze, on 21st May 2021.
The 34-year-old has modelled for the likes of Tatler, Vanity Fair, Vogue and Love, and is now best known as a DJ and member of electronic rock band The Big Pink.
Once known as a wild party girl who stepped out with her high society pals for shindigs, Lady Mary celebrated two years sober in 2020.
Having fun? Cara certainly appeared to be enjoying her birthday celebrations, as she indulged in a plate of cake frosting
She is the youngest child and only daughter of James Charteris and his first wife Catherine, who is the daughter of Guinness heir Jonathan Guinness, 3rd Baron Moyne.
Like many other grown-up society beauties, Lady Mary spent part of 2020 in the country at her father's estate of Stanway House, in Gloucestershire.
Lady Mary and Robbie married at the country pile in 2012, with the bride cutting an edgy figure in a partially sheer gown.
Party time! A whole host of Cara's pals joined her on the yacht to mark her big day