Prince William Spotted Solo at Duke of Westminster's Wedding

Hugh Grosvenor, the Duke of Westminster, and Olivia Henson tied the knot on Friday, June 7.

Prince William stepped out without wife Kate Middleton for the wedding of Hugh Grosvenor, the Duke of Westminster, and Olivia Henson Friday. The 41-year-old Prince of Wales was spotted outside Chester Cathedral in Chester, England, on June 7, sporting a traditional black morning suit.

The royal reportedly acted as an usher during his longtime friend's ceremony. Grosvenor, 33, is close to many members of the royal family, but William was the member of his direct family to attend the ceremony. His brother, Prince Harry, 39, lives in California with wife Meghan Markle and their children Archie, 5, and Lilibet, 3, which is believed to be the reason for his absence. Prince William and Princess Kate's three kids – Prince George, 10, Princess Charlotte, 9, and Prince Louis, 5 – were likely in school for the wedding.

As for Kate, 42, the princess has been absent from several of her husband's recent public appearances as she privately battles cancer. The mother of three announced in March that she had been diagnosed with an undisclosed form of cancer during an unrelated abdominal surgery several months earlier. She is currently undergoing preventative treatment

"William and I have been doing everything we can to process and manage this privately for the sake of our young family," Kate said in a March video from Kensington Palace. "As you can imagine, this has taken time. It has taken me time to recover from major surgery in order to start my treatment."

She continued, "I am well and getting stronger every day by focusing on the things that will help me heal in my mind, body and spirits. Having William by my side is a great source of comfort and reassurance too, as is the love, support and kindness that has been shown by so many of you. It means so much to us both."

While recovering from treatment, Kate has taken a step back from her public-facing engagements, indicating in March that she would return to her official duties after being medically cleared by her physicians. While some reports have indicated that Kate may return to work in the fall, the royal family has yet to confirm any official timeline. Kate is expected to skip the annual celebration of King Charles III's 76th birthday, Trooping the Colour, next weekend. The king confirmed in February that he has also been battling an undisclosed form of cancer, resuming his public duties back in April.