Queen Elizabeth and Prince Philip are preparing to spend their summer holiday in Scotland with the possibility of reuniting with other members of the royal family. However, Her Majesty and the Duke of Edinburgh will have to be in a "Balmoral Bubble" for their stay in the Highlands to protect them from contracting the coronavirus disease, COVID-19.

The Balmoral Bubble is a health and safety protocol for the monarch and her husband, who are both vulnerable to the virus due to their advanced age. This involves the enforcement of strict social distancing protocols for the staff working in Balmoral and for members of the royal family who may plan to visit the estate this summer as well.

Among the conditions of the Balmoral Bubble include a scaled-down number of royal staff members, who need to quarantine before and after their shifts, similar to the protocols in Windsor. Visitors of Queen Elizabeth and Prince Philip will also not be allowed to stay in the castle but in some other properties on the estate.

Queen Elizabeth and Prince Philip may join the royal family in summer activities outdoors, such as walks, picnics and horse riding. They will, however, be expected to observe social distancing at all times and can't get too much close to the elderly royals.

Prince Charles and his wife, Camilla, the Duchess of Cornwall, recently, left their Balmoral estate in Birkhall to restart their face-to-face royal engagements in London so it's still unclear if they have plans to join Queen Elizabeth and Prince Philip. Prince William and Kate are letting their kids enjoy the summer at Anmer Hall in Norfolk but a quick trip in Scotland might be in the schedule since Her Majesty and the Duke of Edinburgh are staying in Balmoral until October.

Newly-married Princess Beatrice and Edo could visit Balmoral with sister Princess Eugenie and her husband Jack Brooksbank. The York princesses once said that Balmoral is the "most beautiful place on earth" and they believe that their grandmother is her happiest in the Highlands.

But the family reunion will be without Prince Harry, Meghan Markle and Archie. The Sussex family had plans to spend the summer with the Queen and Prince Philip before the pandemic crisis. According to The Times, that plan has been scrapped due to travel restrictions from those coming in the U.S. Prince Harry and Meghan have been staying in Los Angeles with their son since the middle of March.

Buckingham Palace won't comment on who will be joining Queen Elizabeth and Prince Philip, except to say that this summer holiday is a private time for the royal family.