Charlotte Casiraghi sparked pregnancy rumours when she stepped out with a fuller figure than usual at the weekend.
The stunning royal, who is dating French comedy actor Gad Elmaleh, sported an ivory-coloured jacket which seemed to show the beginnings of a baby bump at a show jumping event in Monaco.
While there has been no comment from the Palace, the fashionable royal's stance, with her hands resting protectively by her rounded tummy, suggested that there might be a little one on the way.
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He or she would be the second grandchild for Princess Caroline whose son Andrea Casiraghi and his fiancée Tatiana Santo Domingo welcomed baby Sacha into the family in March.
It seems her mother might have had an inkling too. As the pair lined up to applaud the winners in Saturday's ceremony, she glanced down at her radiant daughter's tummy.
The duo laughed and smiled together as they looked on during the podium ceremony before presenting trophies.
Twitter was aflutter with rumours of another royal baby for Monaco after the photos of Charlotte were published.
Charlotte's beau, 41-year-old Gad is a popular French-born comedy star. He first caught the eye of Monaco's beautiful young royal at the beginning of last year.
Since then their relationship has gone from strength-to-strength with transatlantic visits and most recently a high-profile outing at Monaco's glittering Rose Ball.
On Sunday, Charlotte was joined by Princess Caroline's brother, Prince Albert, which saw the equestrian star slip into a more brightly coloured outfit.
The 26-year-old wore a loose-fighting cobalt number which drifted over the rounded tummy which had been more visible on the previous day.
"It's marvellous to be here for another year, in this incredible scene, by the sea in the heart of Monaco," said Charlotte. "Everyone tells me how impressed they after seeing the tournament."
"It is also a privilege to enjoy seeing the best riders in the world," she added, before concluding. "In short, it is a combination of many things that make this a very special event."
Charlotte surprised royal watchers by separating from her partner of fouryears, Alex Dellal, in 2012. Charlotte and Alex, the son of millionaire property owner Guy Dellal got together in 2007.
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