Torontonians can pat themselves on the back for helping make the relationship between Prince Harry and Meghan Markle possible.

“I think Toronto was really important in the relationship because Meghan could go about Toronto quite freely,” says royal insider and author Katie Nicholl.

Nicholl was in the middle of researching a new unauthorized biography about the 33-year-old prince when “Suits” actress Markle entered the picture, sending Harry on many secret trips to Toronto.

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“I spoke to people who would take yoga and pilates with her and she was just ‘Meghan Markle.’ I think Prince Harry was able to go there pretty incognito,” says Nicholl, who conducted over 100 interviews for her book, Harry: Life, Loss and Love. “They ended up going to a party at Soho House – a Halloween party – and they were able to go undetected.”

With countless hours of interviews, Nicholl says she is impressed with how “normal” their relationship is.

“One of the loveliest things I’ve found out about Harry and Meghan is how normal their courtship was,” she tells ET Canada, explaining that the couple spends a lot of their free time cooking at home and watching Netflix. “Date nights would typically be Meghan cooking a lovely organic supper at Nottingham Cottage and settling down to watch Netflix. Apparently, they watched ‘The Crown’ together.”

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While the couple is getting ready to walk down the aisle in May, Nicholl also looked into the past relationships of Harry. In the course of her interviews and research, Nicholl details why the prince’s previous relationships with his first love, heiress Chelsy Davy, and his more recent ex, Cressida Bonas, didn’t work out.

“I thought it was so interesting to learn that watching Kate on duty at an overseas engagement made Cressida realize she just didn’t have what it took to be a royal bride,” Nicholl explains. “And ironically enough, it was the royal wedding that put Chelsy off. She was at the royal wedding in 2011, she told friends she just knew that it was not a role she was able to fulfill.”

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Nicholl doesn’t expect Bonas to attend the wedding, but wouldn’t be surprised to see Davy there since she and the prince have remained good friends since their split.

As for their first official travel plans, the author says Canada is likely high on the itinerary, just as it was for Prince William and Kate Middleton, who made Canada their first official overseas visit shortly after their 2011 wedding.

“They’ll be expected to travel and go on a tour. Canada I’m sure will be a top destination,” Nicholl says. “Everything I’m hearing is they’ll visit Canada soon after the royal wedding.”