Kate Middleton and Prince William are on a secret holiday!

Kate Middleton and Prince William along with their children — Prince George, Princess Charlotte and Prince Louis — have secretly flown to the serene island of Mustique for a family holiday. This is the first time that the Duke and Duchess are travelling as a family of five. However, for William and Kate, there is another special reason too — their eldest son George is turning five this Sunday.

Though there are no official photographs of the royals, social media users are already raving comments about the royal holiday. Royal blogger Tea Time with the Cambridges revealed that the Cambridges were spotted boarded a private plane from the St Lucia airport in the Caribbean to arrive at their next destination.

It has also been reported that Kate's family — including her parents Carole and Michael — are also spotted along with the couple. However, it is still unclear whether Kate's sister Pippa Middleton, who is expecting her first child, has joined them. Some reports claim that Pippa and husband James Matthews are likely to join the family soon to celebrate their babymoon.

It must be noted that Kate's parents are a regular visitors to Mustique. Every year the couple escape the January winter to celebrate Carole's birthday. But, this year, they seem to have postponed their trip to celebrate with their grandchildren.

Known for its virgin beaches, Mustique is a luxury small island in the Caribbean Sea, belonging to Saint Vincent and the Grenadines. A favourite among many celebrities, the island boast 100 luxury villas with a strict no-fly zone over the area.

Remember Kate's topless sunbathing controversy at the French Island in 2012? Ever since then, the couple is extra conscious on their personal life.

Now, the no-fly zone would give Kate and William the much-needed time to get soaked up in the Sun and relax with their family.