The Prince and Princess of Wales celebrated Mother's Day on Sunday by sharing new photos of Princess Catherine alongside Prince George, Princess Charlotte and Prince Louis.

Kensington Palace shared the photos on Instagram in honor of Mother's Day in the U.K., celebrated on March 19.

The photos, snapped by royal family photographer Matt Porteous, showed the princess relaxed in a tree with her three children: Prince George, 9; Princess Charlotte, 7; and Prince Louis, 4.

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Another photo of Kate swinging around her youngest child, Prince Louis, dressed casually in an eyelet white top and blue jeans.