Sarah Ferguson sent a subtle message to Prince Harry and Meghan Markle.
She appeared on Loose Women On Wednesday to raise awareness about skin cancer after being diagnosed with malignant melanoma earlier this year.
The Duchess was also asked for updates on the Princess of Wales and King Charles. Buckingham Palace announced in February that King Charles had been diagnosed with a form of cancer.
The monarch resumed public duties in late April with an engagement at the Macmillan Cancer Centre in London, where he discussed his treatment.
In March, the Princess of Wales revealed that cancer was detected during tests following significant abdominal surgery earlier in the year. Princess Kate released a video message confirming the diagnosis and sharing that she had undergone preventative chemotherapy. She has not yet returned to public duties as she continues to focus on her health.
Sarah Ferguson said regarding Kate and the King: "The great example they have set is that they have spoken about it themselves.
"Princess Catherine was so brave and courageous. [Kate is] such a wonderful mother and an inspiration to all of us."
The Duchess of York also stressed the importance of family unity amid the ongoing feud between senior royals and Prince Harry and Meghan Markle.
Ferguson said: "Family unity is key, we should all unite in order to really feel better."
The Duke and Duchess of Sussex have not been invited to the Trooping the Colour event on June 15 for the second year in a row.
The couple will also miss the Duke of Westminster's wedding on Friday, June 7 despite Hugh Grosvenor being their son's godfather.
Harry and Meghan declined an invite to the wedding to avoid an awkward reunion with Prince William, who will be an usher at the event.
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