Members of the British Royal Family normally send back greeting cards and letters to fans who ship their greetings to the family, especially on Christmas. But, almost a century ago, Queen Elizabeth II and Prince Philip sent never-been-seen Christmas cards to their royal staff with their inked signatures.

According to People, these cards were "sourced" from a couple who worked at the Balmoral Castle in Scotland. The wife used to be a staff inside the house and her husband on the estate.

No one knows the reason behind why personalized Christmas cards were sent to the couple each year dating back from 1947 up to 1972. Even so, the publication noted that Queen Elizabeth II and Prince Philip may have very well-regarded the couple staff during those times.

The first of these cards was dated 1947. It came with a picture showing the then-Princess Elizabeth, her sister, Princess Margaret, and their parents, the Queen Mother and King George. Quite amusingly, it was signed by the king and the then-princess.

A decade after the first card, the royals started to send colored photos in their Christmas cards. In 1957, it showed a colored picture of Queen Elizabeth II and Prince Philip, along with their two kids, Prince Charles and Princess Anne. It was signed by the royal couple with the signatures reading, "Elizabeth R and Philip."

The last card on the set was dated 1972. It features a photo of the Windsor-Mountbatten family, which, at that time, mainly included the Queen and the Prince Consort, along with their four kids, Prince Charles, Princess Anne, Prince Andrew, and Prince Edward.

Today, these Christmas cards are now up for auction. As per Marie Claire, royal memorabilia collectors will find these items "appealing." Aside from the fact that they come with personalized "inked" signatures, they all featured "never-been-seen" photos of the royal family.

It was also noted that viewing the cards is currently available on the official website of Rowley's Antiques and Fine Art Auctioneers. The prince range of each Christmas card is estimated to be around $130 up to $200.

While Queen Elizabeth II and Prince Philip may have put an end to sending personalized and inked Christmas cards, as far as the public is concerned, the Christmas traditions of the royal family still continue today.

Based on reports, members of the family normally arrive in the afternoon of the day before Christmas in Sandringham. During the eve, they would all open their Christmas gifts. By the "big day," they would head over to the church and return to the estate for a fine lunch.