She's currently enjoying a holiday on the secluded Caribbean island of Mustique, but it seems that the Duchess of Cambridge still isn't safe from the prying eyes of the paparazzi.
According to the The Mirror, Kate has been pictured strolling along the sands in a bikini, with her growing baby bump clearly visible.
Although the pictures will not be published by the British press, it seems likely that they will spark a bidding war in the US, Australia and Europe, where they could fetch more than £250,000.
These new pictures are said to show Kate walking in the surf with her husband, Prince William. Other pictures are believed to show her sister Pippa, also in a bikini.
It's not clear if the photographer was on the island, which offers high levels of security to guests, or whether the pictures were taken from a boat offshore.
A Royal aide told the The Mirror: "This is unfortunate. They get absolutely no privacy whatsoever."
According to the Daily Mail, the Royal couple are staying in a £5million house on Mustique, which boasts a private cinema, gazebo and 64ft infinity pool. Kate's parents, and her sister Pippa, are staying nearby.
The five-bedroom house usually costs £19,000 a week to rent, but it is not known if the couple have been charged for their stay as it is owned by some close friends of the Middleton family.
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