Kate Middleton‘s surgery and subsequent cancer announcement elicited millions of well-wishes from fans worldwide. However, while many royal followers took to social media to share their support, some chose to write down their thoughts and mail them to the princess directly

One royal fan was surprised by a “beautiful” response from Kensington Palace. As she recovers from surgery and continues medical treatment for her cancer diagnosis, Kate Middleton appears to be reading the many letters sent to Kensington Palace. Some of these well-wishes are receiving a personal response from the family’s most popular royal.

X user Allexmarie posted details of a “surprise” letter she received from Kensington Palace. It was in response to a note she sent Kate after her January surgery. She shared, “Back in January when we were informed our beautiful Princess of Wales had undergone surgery, I sent her a card with our (my family and I) sincerest best wishes for healing and, of course, an abundance of love. Today, I received this beautiful acknowledgment, and I can honestly say I shall treasure this my entire life.”

“The envelope has Kensington Palace on the back. LOL, hubby thought he was going to have to get his suit out for a garden party (silly him), but he is just as blown away as I am to receive this beautiful and much-treasured card. Continued prayers and healing to our beautiful Princess of Wales,” her post concludes. The royal family receives thousands of letters every day to the royal residences. They reportedly read many of them.

In the comments section of her post on X, user Allexmarie shared the address to which she mailed her letter. She sent it to: HRH The Princess of Wales, Clarence House, London SW1A 1BA United Kingdom. According to the royal family website, there is a proper way to address cards to the royals. They suggest using the following format. If you wish to write a formal letter, you could open it by addressing King Charles as ‘Sir.’ If you want to, at the close, you can add, ‘I have the honor to be, Sir, Your Majesty’s humble and obedient servant.’

However, the royal family website says this traditional approach is optional. Royal followers should be able to write in whatever style they feel comfortable with. One of King Charles’s private secretaries shows him almost all of his correspondence on a daily basis. He reportedly takes a “keen interest” in the letters he receives. The royal family website shared tips and tricks to ensure a response from King Charles and other senior royals. Letters with the following topics will likely not receive a response.

“As a constitutional Monarch, His Majesty does not intervene in political or personal disputes. Letters asking him to do so will receive a standard reply to this effect,” it reads. The message concludes, “For security reasons, the Correspondence Team are unable to accept any unsolicited gifts which are sent to The King.”

Letters to King Charles can be addressed directly to him. Royal followers should use the following location and wording: His Majesty The King, Buckingham Palace, London SW1A 1AA. Fans from the United States should add an international stamp, available to purchase at post offices, for the mail to make its way to the royal family.