You know when your mate gets a new partner and they start changing; take up running, drink less, suddenly decide they're going gluten-free or vegan? Just attempting those few changes to try and make themselves a better person, less of a mess.
Well, even princes aren't immune to that. In recent weeks, the newly engaged Prince Harry has been spotted in full workout gear after training at his gym in Chelsea.
And, according to source close to the Palace, Harry has also decided to pack in smoking as his new (non-smoking) fiancee Meghan Markle moves in with him.
"You smell like an ashtray, darling." Credit: PA
The Prince has been spotted smoking several times and is said to be a bit of a social smoker, despite the fact his dad, Prince Charles, reckons it's a 'filthy habit', the Daily Mail reports.
According to reports, Harry got into smoking at school - the golden era of peer pressure, even when you're a prince, apparently - and then got back into it during his time in the armed forces - which I've never been a part of, but can imagine is also quite heavy on the peer pressure.
At one point, he was said to have a 20-a-day habit. Tut tut.
A young Harry, probably hiding some cigs in his uniform here. Credit: PA
But, I mean, there are worse habits for a royal to have: Henry the Eighth beheaded two of his wives, for example.
An insider told the paper that not only has he vowed to give up smoking, he's also banned anyone smoking when they come to pay the couple a visit in their new place in Kensington Palace. Very strict, that's dedication. Although, if he's recently quit, the last thing he needs is someone lighting up near him, I guess.
The source told the paper: "Harry has promised no smoking at all at home. It's not nice for Meghan as a non-smoker.
"So, there's no more hanging out of the window for a quick puff. Harry has quit for Meghan."
Well, Charles will be pleased and presumably Meghan will be too. But I think the real test will come when he's 15 pints deep on his stag do, won't it?
Source: Daily Mail