In 2008, President Barack Obama was elected as the new President of the United States of America; at the time, his and Michelle’s daughters, Malia and Sasha, were aged just nine and six, respectively.

For the past eight years, the Obama girls have lived their lives under the harsh glare of the media – flourishing in their new roles as the country’s First Daughters, and grown into incredible young women.

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However, in just a few weeks, their father will leave his post as POTUS, ushering in a new era under Donald Trump – and, for the first time in almost a decade, Malia and Sasha, now aged 18 and 15, will leave the White House and find a new home elsewhere.

Thankfully, they have a wealth of advice on how to embrace life as a former First Child in the form of Barbara Bush and Jenna Bush Hager.

Eight years ago, the Bush twins (whose grandfather, George H. W Bush, and father, George W. Bush, are both former Presidents) were there to welcome the Obama girls into their new home, show them the bedrooms which had been their own, and show them the best stair rails to slide down in the White House.

Now, once again, they are on hand to help Malia and Sasha adjust to their new lives, in the form of a powerful open letter published on Time.

“You are about to join another rarified club, one of former First Children—a position you didn’t seek and one with no guidelines,” they write.

They went on to advise Malia and Sasha to “never forget the wonderful people who work at the White House”.

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“Our greeter as 7-year-olds at our grandfather's Inauguration was Nancy, the White House florist, who ushered us in from the cold,” they revealed. “She helped us make colourful bouquets of winter flowers for our grandparents' bedside, [and] twenty years later, Nancy did the flowers for Jenna's wedding.

“Cherish your own Nancy.”

Barbara and Jenna added that they stay in touch with the Secret Service agents who protected them during their own father’s presidency – despite the fact that, as teens, the constant presence of armed guards was incredibly irritating.

“They were part of growing up for us: there for first dates, first days, and even an engagement and honeymoon.

“We know it wasn’t always easy – the two of you and the two of us were teenagers trailed by men in backpacks – but they put their lives on hold for us.”

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They also advised Malia and Sasha to “enjoy college” and “make mistakes”, because, now that they don’t “have the weight of the world on your young shoulders anymore”, they can finally do what makes them happy.

However, while they want the girls to have fun, the Bush sisters warned the Obamas to be careful about the people they share their hearts and secrets with.

“Continue to surround yourself with loyal friends who know you, adore you and will fiercely protect you.

“Those who judge you don't love you, and their voices shouldn't hold weight. Rather, it's your own hearts that matter.”

The Bush sisters added: “Take all that you have seen, the people you have met, the lessons you have learned, and let that help guide you in making positive change. We have no doubt you will.”

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However it was the final few lines of Barbara and Jenna’s letter that truly struck a chord with readers everywhere.

Acknowledging the pressure that Malia and Sasha have faced during their past eight years in the White House, they said: “You have listened to harsh criticism of your parents by people who had never even met them. You stood by as your precious parents were reduced to headlines.

“Your parents, who put you first and who not only showed you but gave you the world. As always, they will be rooting for you as you begin your next chapter. And so will we.”

You can read the full letter here.