How Kate Middleton has changed since becoming a mother

The Duchess of Cambridge has just celebrated her milestone 40th birthday, but a lot has changed since she first joined the royal family.

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In the last decade, Duchess Kate has welcomed three children with husband Prince William; Prince George, eight, Princess Charlotte, six, and Prince Louis, three. Behavioural expert Darren Stanton, speaking in association with Be My Bet, has analysed how the royal's maternal side has evolved in recent years, arguing that her body language has matured since becoming a mother.

WATCH: Duchess Kate joined by her children for adorable video

The main difference is how hands-on Kate is with her children, especially in comparison with historical footage of other royal mothers such as the Queen and Princess Anne.

READ: Prince William and Kate Middleton's sleeping arrangements are so different from everyone else's

"Historically, the royal children have been chaperoned by staff during public engagements, but Kate tends not to do that and both her and William are often seen hand-in-hand with their brood - choosing to be present and hands-on," Darren tells HELLO!.

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kate-middleton-prince-george-cute

The royal is a hands-on mum - a stark contrast to royal mums of the past

Her body language speaks volumes of her close rapport with her children, while also making her appear more relatable and down to earth to royal fans.

Darren explains: "In many photos and video clips, Kate is seen kneeling down to the height of her children when she is talking to them - a gesture that is both nurturing and protective."

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kate-middleton-princess-charlotte-naughty

Duchess Kate isn't afraid to chastise her children in public

Kate has also been seen to chastise Princess Charlotte in the past, in photos where her daughter was seemingly misbehaving.

"While other royals would never have been happy to be seen in this light, Kate's body language remains open and transparent," the body language expert adds.

kate-middleton-prince-george-mother
kate-middleton-prince-george-mother

The Duchess of Cambridge's body language 'remains open and transparent'

"She seems happy to be seen as a relatable mum, dealing with all things parents would usually deal with while raising three young children - what you see is what you get with her."

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Darren Stanton is a former police officer with Derbyshire police with a degree in psychology, who used his expertise to uncover the truth when interviewing hundreds of suspects.

Known as 'The Human Lie Detector', he has appeared on The One Show and This Morning as well as working with Robert 'Judge' Rinder.

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