PRINCE Harry thanked Scottish selkies after he and the Duchess of Sussex discovered they were expecting their first child.

In his new memoir, Spare, which was released on 10 January, Harry recalled swimming and singing with seals near Castle Mey in Caithness before a positive pregnancy test confirmed the Duchess was pregnant with their first son, Archie.

The Duke of Sussex wrote that his father had shared stories with him and Meghan earlier in the visit to Scotland, one of these about Scottish mermaids taking the form of seals, and being spotted swimming near the castle.

Charles had advised: “So when you see a seal, you never can tell … Sing to it. They often sing back.”

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Selkies are mythological beings capable of changing from seal to human by shedding their skin.

They are found in numerous Celtic and Norse folktales, and after shifting are described as seal maidens. Tales often revolve around female selkies being coerced into relationships with humans by someone stealing and hiding their sealskin.

Harry wondered if his father had implied selkies could grant wishes. This hopeful reflection follows the Prince revealing insight into the couple’s difficulty to get pregnant, with them being recommended doctors by friends who had helped them conceive.

The Prince shared a snapshot of him and his wife going to the beach in front of the castle afterwards and seeing “a pair of soulful eyes” in the sea. Harry began singing, Meghan joined, and the seals apparently sang back.

Harry proceeded to take off his clothes and swim with the seals, taking part in what he described as “a seal opera”.

He was later advised by a member of the royal staff that this was “ill-advised” due to the northern coast of Scotland having killer whales in the waters.

In the next chapter of the book, which sold 1.4 million copies on its first day of release, the Duke said Meghan took a pregnancy test at Nottingham Cottage and they were overjoyed it came back positive. After the result, he wrote: “I thought: Thank you, selkies. I thought: Thank you, Mummy.”

Scotland features throughout the Prince’s debut novel regularly, with several memories of family time being spent at Balmoral and other locations around Scotland.

Harry recalls deer stalking at Balmoral, Scottish peat dying water slightly brown and the Scottish landscape.