Both were middle-class commoners when they married into their respective royal families.
So, perhaps comparisons between Queen Mary and our own Princess of Wales were inevitable.
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He beamed for photos while standing next to Prince Christian, who waved to fans.
Queen Margrethe, 81, looked elegant in a coral coat dress, a matching fascinator, pearl jewellery and court shoes.
Polished: Prince Christian (pictured next to Crown Prince Frederik), 15, looked sharp in a crisp white shirt, a tailored blue suit, a coordinating vest and tie
Family: Keeping a close eye on her youngest children, Prince Vincent (centre), 10, and Princesses Isabella, (next to Prince Vincent), 14, and Josephine, 10, was Crown Princess Mary, 49
Elegant: Crown Princess Mary donned a blue patterned frock with billowing sleeves and pointy-toe nude heels. Pictured also is Princess Josephine