Due to the COVID-19 pandemic, Her Majesty had to "make some difficult decisions" about who would attend her husband's funeral, since there was a 30-person limit, a Buckingham Palace rep said. "We are dealing with a family funeral and at its heart it is still a family event."
The spokesperson did not reveal whether the Duke of Edinburgh was involved in choosing who would attend his funeral before his death on Friday, April 9.
The 99-year-old will be laid to rest at St. George's Chapel in Windsor Castle. All attendees will wear masks in the chapel, and those taking part in the funeral procession will only wear masks when they enter the chapel.
Queen Elizabeth II will be joined by her and Philip's children — Prince Charles, Princess Anne, Prince Andrew and Prince Edward — as well as Charles' wife Duchess Camilla, Anne's husband, Timothy Laurence, and Edward's wife Sophie, Countess of Wessex.
Philip's eight grandchildren and their partners will also be in attendance, which includes Prince William and wife Kate Middleton; Zara Tindall and her husband, Mike; Princess Eugenie and her husband, Jack Brooksbank; and Princess Beatrice with her husband, Edoardo Mapelli Mozzi.
In addition, family members from both the Queen and Philip's side will be in attendance, as well as Penelope Knatchbull, Countess Mountbatten of Burma — she married into the royal family when she wed Norton Knatchbull, 3rd Earl of Mountbatten.
While the funeral is scaled-down due to the pandemic, former palace spokeswoman Ailsa Anderson told PEOPLE: "Ironically, it is probably how he would have liked," adding: "No fuss, no bother. Right through his life, he never knew what all the fuss was about."
And hopefully there won't be any fuss, since OK! confirmed that William, 38, and Harry, 36, will not walk together at the funeral — their cousin Peter Phillips, who is Princess Anne's son, will be walking between the brothers.
Apart from making the tough decisions on the guest list, OK! reported that the Queen also decided on the attire for the event, banning military outfits.
"It's the most eloquent solution to the problem," a military source explained, as Harry was stripped of his three military titles when he and Meghan stepped back from their senior royal duties last year.
To avoid any conflict, the Queen insisted all senior male royals simply wear suits and ties, since the funeral should be about Philip and not the internal tumultuous relationships between the royals.
"This is obviously very sensitive," royal expert Richard Fitzwilliams explained. "Anything that distinguished the brothers in that way, which would be so obvious for anyone watching, would probably be avoided. The whole thing we do not want is any form of rift."