Kate Middleton will turn 40 on January 9. But for royal expert Duncan Larcombe, the Duchess of Cambridge's celebration will be nothing like that of the Duchess of Sussex.

Meghan Markle used the occasion to launch a new charity based on mentoring and involving big-name actresses like Melissa McCarthy, Adele, and Stella McCartney, but Larcombe imagines that Middleton will not make a big deal of the occasion.

"Kate and William are not the kind of people who leave their children at home and go out to celebrate on their own," Larkom tells OK!

"I think Kate's birthday, like Christmas, will be low-key and focused solely on family matters."

But just because this birthday won't be a big party for Middleton doesn't mean she hasn't celebrated birthdays in jet-setting style in the past. Larkom explains, "Long before we were married, and long before we had children, it was not uncommon for William to take Kate out for her birthday, usually to a ski resort, but once or twice to the Caribbean."

"The first photo of them kissing was taken when Kate was quietly celebrating her birthday with William at the Klosters ski resort in Switzerland. [But that was then, and it is not Kate's style to want to throw lavish parties for friends and family. Nor would it be like a VIP trip to a fancy restaurant in the West End."

"The only thing that would have made her feel comfortable was a trip to a restaurant in the West End.

So now we know what the Duchess' birthday won't be like, but what will it actually be like?""I think we can expect Kate to be deliberately low-key, no fuss and a firm emphasis on family," the expert speculates.

Larkom also does not expect Middleton to announce any new initiatives, unlike Markle did when she was 40. 'I would be very surprised if she announces anything,' he said. 'Firstly, it's not her way of doing things, and secondly, because of the obvious comparisons to Meghan and the continuation of this awful one-upmanship that the Palace is so keen to avoid.'

"Kate is already an established member of the royal family and there is no need to announce anything. In any case, she has already made several statements about her childhood and mental health since we released her from captivity"

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Larkom also has a theory about who Middleton surrounds herself with on her birthday. 'She will especially want to see her parents and siblings. But I think Kate would consider her birthday, even if it is at 40, to be none of her business except to herself and her family."

"The days of William partying all night at Windsor Castle are long gone. Instead, the Duke and Duchess of Cambridge are aging gracefully. Sounds good to me.