Meghan Markle and Prince Harry will be christening their son, Archie Harrison, this weekend. However, a very important member of the royal family will be absent from the private celebration, and it’s allegedly because the couple made a big mistake when they chose a date.

According to reports, when the Duke and Duchess of Sussex christen their son, his great-grandmother, Queen Elizabeth II, won’t be in attendance. Instead of attending the service at Windsor Castle, the Queen will be spending the weekend at her estate in Sandringham with her husband, Prince Philip. As it turns out, according to the Daily Mail, the reason behind her lack of attendance comes from the couple’s choosing a date, but not consulting the other members of the family’s calendars first.

According to a source, the service was initially supposed to be held on July 5, however, it was moved in order to accommodate Prince Charles, who was also going to be unavailable to attend then. However, the Queen had her plans with her husband in her diary for a long while, and following several engagements in recent weeks, she expects to still keep the relaxing plans she had. However, despite not being in attendance, she is allegedly still happy for the couple and understanding of their decision to christen their son this weekend.

“They went to her office with the date and a collective decision was made. The Queen has had the US state visit and Holyrood Week in quick succession and has had this weekend with the Duke of Edinburgh in her diary for a long time,” a Buckingham Palace source allegedly told Daily Mail. “Their office knew that she wouldn’t be able to attend and it was agreed that it would be a nice touch as Her Majesty wouldn’t be able to attend and it was agreed that it would be a nice touch as Her Majesty wouldn’t be in the official photographs. The original date of Friday was changed to Saturday to accommodate the Prince of Wales, who is, after all, Archie’s grandfather.”

“While this was the best weekend for friends and family coming over from the US, they did just really want to hold the christening as soon as possible, before everyone disappears for the summer,” the source continued. “As a family they took a collective decision that this was the best option.”

However, an additional source also spoke to the publication and revealed that they felt the event could have been planned better to accommodate her Majesty since it’s no secret that her schedule is sometimes filled up a year in advance.

“There is huge support for the couple in not wanting to conform to tradition. They are young, they are striking out on a different path from other members of the Royal Family and there is enormous goodwill for them,” the second source said. “But they shouldn’t do that without regard for tradition. Her Majesty was already scheduled to be in Scotland for her annual Holyrood Week and had a prior engagement at the weekend, There is a feeling amongst some that they should have been more accommodating about the date.”

The couple has also received criticism in regards to their son’s christening over the fact that it will be a private ceremony and the only photos that will be released are the official ones they allow to be seen by the public. In addition, they’ve been criticized over their decision to keep the identity of Archie’s godparents private.

Queen Elizabeth II
Queen Elizabeth II is seen at the Chichester Theatre while visiting West Sussex on Nov. 30, 2017, in Chichester, United Kingdom. Getty Images/Stuart C. Wilson