The Middleton family showed their support for the Duke and Duchess of Cambridge as they attended a carol service often attended by their daughter Kate and Prince William.
With William, 37, out of the country on a tour of Kuwait and Oman and Kate attending an outing with school kids in Buckinghamshire, Carole Middleton and Kate’s sister Pippa Middleton and her husband James Matthews attended a concert that honors a cause that was set up in the name of a late close friend of William and his brother Prince Harry. Kate's family has been regular attendees over the years.
The Henry van Straubenzee Memorial Fund helps schools in Uganda, Africa, and was named for one of the princes’ school friends who died in a car accident. Both Prince Harry and William are patrons of the charity.
The princes grew up close to the van Straubenzee boys. Henry was a classmate at the Ludgrove prep school with Prince Harry, while William is friends with Henry’s older brother Tom.
RELATED: Kate Middleton Shares Secrets of Her Family's Palace Christmas Tree
The strength of the two families’ bonds has been underlined when William and Kate chose Thomas to be a godfather to Princess Charlotte. Harry, 35, and Meghan, 38, meanwhile picked Thomas’s younger brother Charlie as one of the godparents to their son Archie.
At the 2011 carol service, Harry praised his friend's “love of life and sense of fun” and sometimes “inappropriate sense of humor.” He thanked the charity, which was set up by Henry’s parents Alex and Claire, for “keeping the memorial of my best friend alive. He would be hugely proud of what you have done in his legacy.”
Last year, Meghan – who was pregnant with Archie at the time — gave a reading from the poem “Our Deepest Fear” by Marianne Williamson at the Christmas carol service.
Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more!
The 2018 event event also marked the first times that James Middleton had publicly stepped out with Alizee Thevenet, who became his fiancée in October.