The Queen is both a devoted monarch and mother to her four children, Prince Charles, Princess Anne, Prince Andrew and Prince Edward.
It's fascinating to see the difference in her behaviour between public engagements and when she's more informal at ease with her family, as body language expert Darren Stanton reveals below.
WATCH: The Queen's 70 year reign in pictures
Darren has taken a look back at the Queen's reign, on behalf of Betfair Casino, ahead of her Platinum Jubilee and analysed her body language from over the years.
The Queen with the late Prince Philip and their children
He reveals: "The only time we have seen a change in the Queen is when she has been surrounded by family.
"From limited historical footage that exists of her in an informal setting, it is clear that the idea of family has always been the most important nucleus of her life. There are plenty of moments where she and Prince Philip are playing with the children and she appears to show a very strong connection with Charles - maybe because he was her first son.
"It’s clear she is immensely proud of him. She relaxes her usually stiff posture and clearly comfortable at home, we see her laughing and openly playing the role of the entertainer."
The Queen with baby Prince Charles
Darren says that this relaxed behaviour changes when the monarch is in a more formal work setting.
He observes: "When in public with her children, however, this openness disappears as the Queen tended to keep her family life private. She demonstrated this desire for instance on international trips where she would pass her children to the staff if they appeared to be tired or getting a little unruly - instead surging ahead with Philip and leaving her brood with their aides.
"This is in direct contrast to nowadays, as we regularly see William and Kate with the Royal children playing and even chastising them when appropriate. They are very happy for the world to see them in that way, whereas years ago it wasn’t so normal for such behaviours to be visible.
"Instead, the Queen has kept a very divisible line between her family and her duty."
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