The Dukes of Sussex and Cambridge have spoken about their many inherited traits from Prince Charles. However, one particular trait Harry, 37, has adopted from his father leaves his wife Meghan Markle, 40, confused, the Prince has said.

       Speaking in a 2018 BBC documentary, the royal stated he is “obsessed” with turning off the lights - a habit picked up from his environmentally conscious father.

       “He's a stickler for turning lights off,” Harry said, speaking about Prince Charles in the BBC documentary called Prince, Son and Heir: Charles at 70, honouring his father and featuring several members of the Royal Family.

       “And that's now something that I'm obsessed with as well, which is insane because actually, my wife goes 'Well, why turn the lights off? You know it's dark',” the royal continued.

       “I go 'we only need one light, we don't need like six', and all of a sudden, it becomes a habit and those small habit changes he's making, every single person can do.

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       “And I think that's one of the key lessons certainly that I felt that he taught us.”

       Prince William added he is also “obsessed“ with turning off the lights in the house - a trait that the whole family now shares.

       “I know I've got serious OCD on light switches now which is terrible,” the Duke of Cambridge said.

       The brothers gained another habit from Prince Charles, and Prince Harry revealed he was even mocked for it in school.

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       The 37-year-old royal said he would "get taken the mickey out of" at school as a result of his habit of picking up litter.

       “I used to get taken the mickey out of at school for just picking up rubbish,” the Duke said.

       “I don't go consciously looking for it. When you go for walks anywhere, if you see something, it stand out, you pick it up.

       “It's like I've literally done this because I'm programmed to do it, because my father did it.

       “Actually, we should all be doing it.”