Princess Eugenie and Jack Brooksbank. Picture: Bang Showbiz

Robbie Williams' daughter will be a bridesmaid at Princess Eugenie's wedding.

Buckingham Palace has announced that Robbie's six-year-old daughter Theodora Williams - whose mother is Ayda Field - is among the wedding party when the British royal ties the knot with her fiancé Jack Brooksbank this Friday at St George's Chapel in Windsor Castle. 

Prince William and Duchess Catherine's children, five-year-old Prince George and three-year-old Princess Charlotte, will serve as pageboy and bridesmaid.

The bride's sister, Princess Beatrice,30, has been confirmed as the maid of honour, while Jack's brother Thomas Brooksbank will act as best man.

Other bridesmaids include Savannah, seven, and Isla, six, the daughters of Peter and Autumn Phillips, four-year-old Mia Tindall, the daughter of Zara and Mike Tindall, and Maud Windsor, five, the daughter of Lord and Lady Frederick Windsor who is also Princess Eugenie's goddaughter.

Meanwhile, six-year-old Louis de Givenchy, the son of Zoe and Olivier de Givenchy will be the other pageboy.

The entire day is set to cost a reputed £2 million and will include a fanfare - specifically written for the day - by State Trumpeters and music from Scottish pipers as the couple travel through Windsor.

Robbie and Ayda, Ed Sheeran, Ellie Goulding, and George and Amal Clooney are set to be among the guests, whilst around 1,200 members of the public were selected by a ballot after 100,000 applied for a place in the castle grounds. 

Andrea Bocelli and members of the Royal Philharmonic Orchestra will perform at the ostentatious event, and following the vows the guests will get to eat a £1,000 red velvet and chocolate cake - which was described by Kensington Palace as being "a traditional cake, with a modern feel" - following the wedding breakfast.