A criminologist has revealed the safety tip all parents should know about.

Dannah Eve, from the US, explained the one rule she always swears by, especially when you’re on a family holiday or travelling in a foreign country.

WATCH THE VIDEO ABOVE: The one rule every parent should know about.

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“Whether you’re in a taxi, cab or an Uber, never let your child be the last one out of the vehicle,” Dannah said in a now-viral video.

“Never give someone the ability to drive off with your child still inside the vehicle.”

The child safety expert explained that when she was growing up, her dad always ensured he was always the last one to get out of the vehicle.

“When I was little and even as a young teen, my mum got out first, then my dad would lead me to my mum and get out right behind me,” she recalled.

“A very simple thing to do that can become second nature, protect your child, and make it so they’re not an easy target.

“Even if it means your kids have to crawl over you to get out of the car first, make sure they are doing so.

“Always practice situational awareness, always protect your kids.”

Dannah has degrees in both criminology and psychology and is known for her child safety tips and tricks.

Her video has received more than four million views — with people weighing in on her child safety tip.

“Such an excellent safety tip,” said one.

“I never thought of this, the world is so dangerous,” said a second.

“So, so important, I sent this to my husband,” added another.

However, some were divided over her rule.

“This is just common sense,” one said.

Another suggested: “This makes everybody so crazy and paranoid.”

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