Prince George and Princess Charlotte Were 'Incredibly Well Behaved,' Says Funeral Attendee Mark Tewksbury

Prince George and Princess Charlotte were "incredibly well behaved" at Westminster Abbey, according to one attendee at the monarch's state funeral.

Mark Tewksbury, a member of the Order of Canada — part of a three-person delegation from that country to attend the service, including actress Sandra Oh and musician Gregory Charles — had a bird's eye view of the procession into the church, and observed the young royals, he tells PEOPLE.

"They looked like really incredibly well behaved kids but a little like kids, a little like, 'wow this is a lot,' " Tewksbury says. "For little Prince George, this will be him one day and he doesn't really know that yet. And then I thought, 'Ah, he's just lost his great-grandmother.' "

Tewksbury, an Olympic swimmer who won the gold medal for Canada in the 1992 Summer Olympics, participated in the Orders of Chivalry procession along with Oh and Charles.

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Peter Byrne/PA Images via Getty The Duchess of Sussex, the Queen Consort, Prince George, the Princess of Wales, Princess Charlotte and the Countess of Wessex leaving the Queen's state funeral

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"It was just a spectacle, a who's who of heads of countries," he says of the procession, which included 51 delegates "that are really prominent in the British realm."

He continues, "And then to walk in the honor procession, all eyes on us!"

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Tewksbury was among one of the first Olympic athletes to openly come out as gay, and says his human rights record for the past 30 years "is what got me the highest order of the companion," a distinction given to prominent members of Commonwealth realms. Tewksbury has spent his post-Olympic years fighting for people with intellectual disability and for the LGBTQ-plus community.

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The former swimmer's path crossed several times with Queen Elizabeth, including during a private audience at the 1994 Commonwealth Games in Victoria, British Columbia.

"She was incredible, she knew I was a swimmer, she loved the Commonwealth and loved how sport brings us together, she was incredibly well-informed," he recalls.

On Monday, as he mourned the queen's passing, Tewksbury says he got emotional during "God Save The King," and that he and Oh were "pinching ourselves the whole time."

"Even movie stars and TV stars get a little overwhelmed in all of this stuff," he says.