Prince Charles Marks First Anniversary of Prince Philip's Death with Rarely Seen Childhood Photo

Prince Charles marked the first anniversary of his father Prince Philip's death by sharing some of their happy moments together.

Clarence House, the office of Prince Charles and Camilla, Duchess of Cornwall, shared three photos on Saturday in a social media post to honor Prince Philip on the first anniversary of his death. The Duke of Edinburgh, the Queen's husband of 73 years, was 99 when he died of old age on April 9, 2021.

One photo was a black-and-white shot from Prince Charles' childhood, taken on the grounds of the royal family's beloved Balmoral estate back in 1955. Prince Charles sits on a swing with his sister Princess Anne as Prince Philip gives them a big push. Queen Elizabeth is also seen in the joyous picture, watching on and making sure one of their pet dogs doesn't get in the way.

Prince Charles also included a photo featuring his wife Camilla with the Queen and Prince Philip from 2016, when the foursome attended the unveiling of a statue of Queen Elizabeth, the Queen Mother together. The two couples share a laugh and exchange smiles in the snap.

The first photo featured in the social media post was a solo shot of Prince Philip with a big grin on his face.

"Remembering The Duke of Edinburgh today, one year since his passing," the post was captioned by Clarence House.

The death of Prince Philip coincides with a special day for Prince Charles and Camilla — their wedding anniversary. The couple married in 2015 at St. George's Chapel in Windsor Castle. Since they were both divorced, they had a civil marriage ceremony followed by a blessing at Windsor Castle instead of a church service.

Prince Charles, 73, and Camilla, 74, did not post anything on social media to mark the anniversary on Saturday, instead, they joined the rest of the royals to honor Prince Philip.

Queen Elizabeth, who will turn 96 this month, and the royal family also marked the first anniversary of Prince Philip's death with a poignant tribute.

She shared a moving poem written by the U.K.'s Poet Laureate Simon Armitage alongside a video montage that features special moments of Philip's life and their life together, including their royal wedding day and the arrival of their four children, grandchildren and great-grandchildren.

"Remembering His Royal Highness The Duke of Edinburgh on the first anniversary of his death," read a message added to the post

The monarch and the rest of the family spent the day privately, PEOPLE understands.

Eight days after Philip's death, a funeral was held at St. George's Chapel in Windsor Castle on April 17 with attendance limited to just 30 family members and close friends due to the COVID-19 pandemic. Attendees included Prince Philip's wife of 73 years (who sat alone due to social distancing precautions, resulting in a heartbreaking image), their four children, eight grandchildren and some of their spouses.

A larger memorial service was held last week at Westminster Abbey, providing an opportunity for representatives of the many charities and organizations that Prince Philip worked with to pay tribute to him. In addition, some of his great-grandchildren — including Prince George, 8, and Princess Charlotte, 6 — were in attendance.

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Queen Elizabeth also attended the Service of Thanksgiving despite dramatically scaling down her public outings in recent months due to health setbacks and mobility issues.