Kate Middleton Is 'Incredibly Grateful' for Lady Gabriella's Help with Her Christmas Carol Service

Yesterday at 06:52 PM

Gabriella marked her first Christmas without late husband Thomas Kingston by assisting Kate with 'Together at Christmas'

Kate Middleton had an extra set of hands working on herTogether at Christmascarol service this year.

The Princess of Wales, 42, wanted the fourth annual service to be focused around love, kindness and empathy — and she asked Lady Gabriella Kingston (née Windsor) to join her team to help, PEOPLE confirms.

Gabriella, the only daughter of Prince and Princess Michael of Kent, played an advisory role around the music performances featured in the Dec. 6 service, PEOPLE understands.

And the 43-year-old royal, who works as a freelance journalist, enjoyed her role and was excited to be a part of the service, a source tells PEOPLE.

Kate "was incredibly grateful for her contribution," the insider adds. 

Related: Kate Middleton Personally Records Special Christmas Message Voiceover for TV Special of Her Carol Concert

Gabriella's role in the service was fitting for the royal, who previously showed off her musical chops in 2020, when she released two songs to benefit music nonprofit Playing for Change Foundation.

In addition to her role in planning it, Gabriella also attended the festive, candle-lit event — which was held at Westminster Abbey on Dec. 6 and airs on Christmas Eve on ITV1 and ITVx in the U.K — along with Princess Kate, Prince William, and their kids, Prince George, 11, Princess Charlotte, 9, and Prince Louis, 6.

The royals gathered at the London church to watch traditional hymns and songs and readings led by the Prince of Wales, Richard E. Grant and more stars, as well as musical performances by guests including Olivia Dean and Paloma Faith. The event also featured a piece by pianist Rosey Chan and a performance by two soloists from The Royal Ballet and students from The Royal Ballet School.

Set to air on Christmas Eve, the Together at Christmas service — which welcomed a total of 1,600 guests, including members from both sides of Kate's family — marks the end of a difficult year for Princess Kate, who announced she was undergoing treatment for cancer in June.

Related: Kate Middleton and Prince William Share Poignant Christmas Card with George, Charlotte and Louis After 'Hardest' Year

In September, Kate shared that she had completed chemotherapy, and the Dec. 6 Christmas concert was her most notable appearance following the news.

For Lady Gabriella, the event marked her first Christmas without her husband, Thomas Kingston, who died in February at age 45. Following the financier's death, a statement was released on behalf of Gabriella, as well as Martin and Jill Kingston, Joanna Connolly and Emma Murray.

"It is with the deepest sorrow that we announce the death of Thomas Kingston, our beloved husband, son and brother," the statement read. "Tom was an exceptional man who lit up the lives of all who knew him. His death has come as a great shock to the whole family, and we ask you to respect our privacy as we mourn his passing."

Earlier in December, a source assured that, though Princess Kate stepped out alongside her family to host Together at Christmas, she is taking a slow, intentional approach while navigating her return to public life amid her cancer recovery.

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"She is focused on herself and her family right now, rightly," a source close to the palace told PEOPLE at the time.

Other friends and sources emphasize that the princess' experience has changed her perspective forever, with an insider close to the royal household telling PEOPLE, "Life-threatening illnesses bring a reconsideration of priorities. She and William have always made it clear that family is the most important thing."

"You can't go through something like that and come out the other side unchanged," the source added. "She is a different person now."

Royal Carols: Together at Christmas airs on ITV and ITVX on Christmas Eve in the U.K. and streams on Britbox in the United States and Canada.