Kate Middleton 'Wrote Every Word Herself' in Speech Revealing Her Cancer Diagnosis, Source Says

Kate Middleton's announcement revealing her cancer diagnosis came from the heart.

“She wrote every word herself,” a palace source confirms to PEOPLE of the Princess of Wales' video speech, which was released on Friday and filmed two days prior in the gardens of Windsor Castle.

A family friend adds, “She wrote the words herself, delivered it personally and wanted to decide when the time was right to hit the world with this news.”

On Friday, Kate, 42, shared her cancer diagnosis in an emotional video message. She said she received the diagnosis following her abdominal surgery in January after post-operative tests "found cancer had been present” and is now in the “early stages” of treatment.

Prince William is said to be “extremely proud of his wife for the courage and strength she has shown not just this week, but since her surgery in January," a royal source says.

The insider added that William, 41, is protective of his family, stating, “Now more than ever he’s focused on ensuring his wife has the privacy she needs to fully recover and that his children are shielded from the understandable interest in the news that has been shared.”

On Saturday, the Prince and Princess of Wales said they were grateful for the wide support they’ve received following the princess’ cancer diagnosis announcement.

A Kensington Palace spokesperson said in a statement that Kate and William "are both enormously touched by the kind messages from people here in the U.K., across the Commonwealth and around the world in response to Her Royal Highness’ message."

"They are extremely moved by the public’s warmth and support and are grateful for the understanding of their request for privacy at this time," the spokesperson added.

In her speech on Friday, Kate began by thanking well-wishers for their support over recent weeks.

She then called her diagnosis a "huge shock" and said that she and William "have been doing everything we can to process and manage this privately for the sake of our young family," referring to their three children: Prince George, 10, Princess Charlotte, 8, and Prince Louis, 5.

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Princess Kate added that "it's taken us time to explain everything" to their kids "in a way that is appropriate for them, and to reassure them that I am going to be okay."

The royal concluded her speech by acknowledging those also dealing with cancer. "At this time, I am also thinking of all those whose lives have been affected by cancer. For everyone facing this disease, in whatever form, please do not lose faith or hope. You are not alone." she said.