Oh Jack! Good luck explaining these photographs with glamorous women in Capri to Princess Eugenie as she's stuck at home with the baby

For most new fathers, life is an endless grind of dirty nappies and sleepless nights.

But for Princess Eugenie's husband Jack Brooksbank, it's clasping a glass of rosé on a vintage speedboat off the sun-kissed Italian coast while surrounded by bikini-clad models.

And he even gets to call it 'work'.

The 35-year-old is spending the weekend on the chic Mediterranean island of Capri, attending a star-studded charity ball under the stars while his wife remains in Windsor looking after their five-month-old son, August.

Mr Brooksbank is a brand ambassador for Casamigos tequila, a sponsor of last night's invitation-only Unicef Summer Gala, where tickets are priced from £8,000 to £25,000.

And ahead of the bash, he spent Friday afternoon aboard the classic 26ft 'gozzo' boat, exploring the caves and grottos dotted around Capri's coast.

For most new fathers, life is an endless grind of dirty nappies and sleepless nights. But for Princess Eugenie's husband Jack Brooksbank, it's clasping a glass of rosé on a vintage speedboat off the sun-kissed Italian coast while surrounded by bikini-clad models. And he even gets to call it 'work'

Joining him were Rachel Zalis – a former editor of Glamour magazine who is now Casamigos's global director, and who soaked up the rays in a black bikini – and Maria Buccellati, a model turned fashion ambassador. 

She wrapped her arm around him as they posed for an affectionate-looking Instagram snap to share with her 14,000 followers.

Also on board was Italian model Erica Pelosini, who Jack guided around the boat by placing a hand on her back. 

The 35-year-old is spending the weekend on the chic Mediterranean island of Capri, attending a star-studded charity ball under the stars while his wife remains in Windsor looking after their five-month-old son, August.

Though she had a towel wrapped around her at the time, she periodically removed it to go topless in full view of Jack and the boat's skipper. 

During the afternoon-long boat tour, Jack dived into the Tyrrhenian Sea to join his three companions as they bobbed gently in the inviting water.

He could occasionally be seen popping on to the boat deck to look at his phone – perhaps checking-in with Eugenie back at home.

Mr Brooksbank is a brand ambassador for Casamigos tequila, a sponsor of last night's invitation-only Unicef Summer Gala, where tickets are priced from £8,000 to £25,000. And ahead of the bash, he spent Friday afternoon aboard the classic 26ft 'gozzo' boat, exploring the caves and grottos dotted around Capri's coast

It is unclear how Jack knows Erica and Maria, but both women are associates of Israeli socialite Hofit Golan, 35, a social media influencer who is well-known for turning up all over the world on yachts belonging to the rich and famous.

She counts Lady Victoria Hervey, an ex-girlfriend of Prince Andrew, as one of her closest friends. Only last week, Hofit was seen yachting with Erica and Maria in Cannes.

A source close to Jack told The Mail on Sunday that Eugenie hadn't joined him on the business trip to Capri because he was 'there to work at the ball'. 

Sources say Jack's job was to keep an eye on the cocktail bar and schmooze with famous guests, who included singers Katy Perry and John Legend and supermodel Heidi Klum.

Mr Brooksbank is said to hate his former nickname of 'barman Jack', which he picked up as he was working a restaurant and wine bar in Central London at the time he met Eugenie in 2010. 

Stowe-educated Jack met Eugenie, now 11th in line to the throne, while skiing in Switzerland, and they married at St George's Chapel in Windsor Castle in 2018.

They now live at nearby Frogmore Cottage in an arrangement which reportedly sees them pay rent to the Duke and Duchess of Sussex.

Joining him were Rachel Zalis – a former editor of Glamour magazine who is now Casamigos's global director, and who soaked up the rays in a black bikini – and Maria Buccellati, a model turned fashion ambassador

During the afternoon-long boat tour, Jack dived into the Tyrrhenian Sea to join his three companions as they bobbed gently in the inviting water. He could occasionally be seen popping on to the boat deck to look at his phone – perhaps checking-in with Eugenie back at home

Also on board was Italian model Erica Pelosini, who Jack guided around the boat by placing a hand on her back

Jack signed up to promote the £45-per-bottle tequila brand in 2016. Casamigos – which comes from the Spanish for 'house of friends', was founded in 2013 by George Clooney, Cindy Crawford's husband Rande Gerber and their friend Mike Meldmans. 

It was sold to multinational drinks giant Diageo in a $1 billion (£720,000) deal in 2017.

The company just announced it has made its millionth case.

Casamigos sponsored last night's ball, which was billed as a 'magical evening in paradise'. 

The night included a 'languorous' cocktail hour, gala dinner and an auction to raise funds for Unicef's programmes helping children in need across the world. 

Items being auctioned included Steve McQueen's 1961 Cooper Formula Junior race car and an Andy Warhol artwork.

Britain's Princess Eugenie and Jack Brooksbank pose with their son, August Philip Hawke Brooksbank