According to the U.K.’schild car seat laws, children from 3 years to 4’5” tall who are under 12 years — which would include George — must “use an appropriate child restraint when traveling in front seat.” George was reportedly in a booster seat.

The country’s laws also state that children of the same age that are seated in the backseat must also be put in a child-restrained seat, if seat belts are fitted. Once a child is more than 4’5”, they must then use a seat belt, although the U.K prefers them to use a booster seat until they reach 5′.

Prince William and Prince George.Tim Rooke/Shutterstock

Prince William, Prince George

However, there are several exceptions to these rules. Should an appropriate child restraint not be available, children over 3 years old can travel in the rear using an adult seatbelt. This exception is for emergencies and unplanned situations only.

If a child between 3 years and 4’5” tall is traveling in a licensed taxi, such as a private hire vehicles or minicabs, they must sit in the rear and wear a seatbelt. Children younger than 3 must sit in the rear with an adult seatbelt should a child restraint not be available.

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Prince George

Children under the age of 3 — which would include George’s younger brotherPrince Louis, 1 — must use an appropriate child restraint in the front or rear of a vehicle.

It is illegal to carry the child in a rearward-facing child seat in the front if there is an active front passenger airbag. The airbag must be turned off or the child seat must be placed in the rear.

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While George arrived to the annual Christmas lunch with his father,Kate Middleton, with daughterPrincess Charlotte, 4, and youngest sonPrince Louisin the backseat.

A source told PEOPLE that bothGeorge and Charlotte are set to make their Christmas Day debutthis year alongside parentsPrince Williamand Kate — but that things could always change.Prince Louismade his big debut at Trooping the Colour this year, but he’s likely too young to join his parents and siblings on Christmas.

source: people.com