A poignant message celebrating all mothers was posted online alongside treasured images, which showed Charles as a beaming baby standing on the Queen’s lap.
In a separate photo, an adult Camilla is seen smiling as she stands behind her elderly mother.
The Twitter post is accompanied by the message: "To all mothers everywhere, and to those who may be missing their mums today, we are thinking of you and wishing you a special #MothersDay."
The Queen died in September aged 96, while Camilla’s mother Rosalind Shand died in 1994 at the age of 72 after a long battle with osteoporosis.
The Princess of Wales also shared photographs of happy family memories to mark the day. The first image shows Kate sitting in a tree with her children Prince George, Princess Charlotte and Prince Louis.
Accompanying the post is the words "Happy Mother’s Day from our family to yours", along with a red love heart. They are all casually dressed and smiling into the camera.
Another photograph shows a smiling Kate as she plays with Louis in her arms.
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