Kate Middleton and Prince William need to get all the rest they can now while there's still time.

The royal parents-to-be, who are expecting their first child later this year, have jetted off to a Caribbean beach vacation for a bit of a babymoon, according to The Sun.

Their destination of choice? The super-exclusive island of Mustique, which William's late relative Princess Margaret used to frequent, and where celebrities like Mick Jagger often spend time.

The royal couple is staying in a posh $28,000-a-week villa, and Kate's parents are reportedly staying in a nearby villa. Cute!

A note to Kate and Wills: Maybe next time you go to Mustique, can you invite us, too?

Source: The SunPeopleUs Weekly