Princess Beatrice has officially celebrated her engagement in true style, hosting a secretive event in one of London's A-list venues - with a bunch of A-list pals in tow.
The royal, who announced her engagement to partner Edoardo Mapelli Mozzi threw the soiree at Chiltern Firehouse in the British city, and along with her mother Sarah Ferguson, there were plenty of famous faces seen making an entrance into the top-secret event.
Earlier in the day, Beatrice attended the Queen's annual pre-Christmas lunch on Wednesday, December 18, where she was spotted arriving by car.
The 31-year-old was there alongside a slew of regal royal family members, including her father Prince Andrew, who is in the troughs of criticism at present after his connection to convicted sex offender Jeffrey Epstein was exposed.
Naturally, many wondered if he would attend Beatrice's engagement party too, however, he was noticeably absent from the arrivals later that night.
Beatrice's mother Sarah Ferguson however, led the A-list pack into her daughter's big event.
Also in attendance were Kate Middleton's siblings, Pippa and James Middleton. The pair came with their respective partners, James Matthews and Alizee Thevenet.
Kate's younger brother and Alizee might have taken some notes during the private event - the pair recently announced their own engagement after around a year of dating.
The two couples made low key entrances, with Pippa going for a dark coloured ensemble. Alizee meanwhile opted for some printed trousers featuring a unique green print.
One of Beatrice's long-time pals Ellie Goulding was also a notable attendee.
Ellie made global headlines in September when she married her long-time love Caspar Jopling in a royal-worthy ceremony in York.
Beatrice, along with older sister Eugenie and mum Fergie were seen at the lavish event - and there's no denying the family is close with the Starry Eyed singer.
That's why it came as no surprise to see Goulding attend Beatrice's 'do in London.
Wearing a black velvet dress featuring large silver buttons, the British singer looked glamorous as she made her entrance.
Other attendees included British singer James Blunt, Ayda Field and even Robert de Niro.
Suffice to say it was star-studded!
Beatrice's sister Princess Eugenie was not photographed attending the event, but that's not to say she wasn't there.
The Express reports that Eugenie was indeed in attendance, and simply may have arrived early to help her sister set things up - explaining why she wasn't photographed with the other arrivals.
Makes perfect sense to us!
WATCH: Princess Beatrice's text to Ellie Goudling about their friendship is so sweet: