Members of the royal family showed support for Prince William this week as Princess Kate has all but vanished from public following her cancer diagnosis.

That's according to Newsweek, which reported that William's cousins arrived at Buckingham Palace on Tuesday to help him host a garden party.

Princess is undergoing "preventative chemotherapy"

The event was organized on behalf of William's father, King Charles III, and featured around 8,000 guests from both the United Kingdom and Commonwealth countries.

Among those in attendance were Zara Tindall and Peter Phillips, both of whom are children of William's aunt, Princess Anne. Also helping the prince with hosting duties were Princesses Beatrice and Eugenie, daughters of Prince Andrew and his ex-wife Sarah Ferguson.

Meanwhile, a spokesperson for Kensington Palace announced on Monday that Kate is undergoing "preventative chemotherapy" and "is not expected to return to work until it's cleared by her medical team."

Kate is not the only royal family member to struggle with cancer, as her father-in-law has been undergoing treatment for prostate cancer since February.

Prince Harry will not attend wedding where William is serving as an usher

One member of William's extended family who did not attend Monday's garden was his brother, Prince Harry, with whom he has been on difficult terms.

Newsweek reported this week that Harry won't be present next month when Hugh Grosvenor, Duke of Westminster, marries Olivia Henson at Chester Cathedral.

The magazine stressed that Harry's absence will be notable given his close relationship with Grosvenor, who serves as godfather to his eldest son.

However, William will be serving as an usher at the wedding and Harry acknowledged during an interview last year with "60 Minutes" that the two now longer speak.

Harry claims William pretended not to know him at school

Harry also alleged in his autobiography "Spare" that William instructed him to pretend they didn't know one another while both were attending the same school.

Prince Harry said his brother Prince William told him when they attended the same high school that he should “pretend we don’t know each other.” https://t.co/OnsmQ13eyM pic.twitter.com/3gRzOQKfyN

— 60 Minutes (@60Minutes) June 4, 2023

"Even when you were in the same school, in high school. Your brother told you, 'Pretend we don't know each other,'" Host Cooper told the prince.

"Yeah, and at the time it hurt. I couldn't make sense of it. I was like, 'What do you mean? We're now at the same school,'" Harry replied.