It’s not often a member of the royal family comes out with a big beauty recommendation (there are rules and regulations surrounding all that jazz, after all, Kate Middleton and Meghan Markle are famously tight-lipped about the beauty products they use) but as soon as one creeps out of the woodwork, word spreads like wildfire. One of the lesser known beauty heroes to grace the royal dressing tables is said to be Beuti Skincare Beauty Sleep Elixir, a natural face oil that is now available in Harvel Nichols . According to Leila Aalam, Beuti's founder, Kate Middleton is a huge fan – so much so that she recommended it to her sister-in-law, the Duchess of Sussex before Meghan Markle moved to the US.

Aalam is an experienced aesthetician who, after suffering from a severe allergic reaction to a luxury eye cream, was on a mission to provide products free of toxic chemicals and irritants that would still deliver results. As a result, Beuti hit the beauty scene in 2015, with the Elixir as its one and only product.

With a whole world of cosmetics and skincare available to them, it says a lot that both the Duchess of Cambridge and the Duchess of Sussex have developed a loyalty to a single bottle of oil

Speaking exclusively to Grazia, Aalam revealed: 'An old friend of mum's has worked in Kensington Palace for going on 30 years. He has seen Harry and William grow up, plays with George and Charlotte, helps them all put up the Christmas tree each year. When I launched the Beauty Sleep Elixir he said "Give me some and I'll hand it over," and he passed some on to Kate to try. The next thing he knew, there were three full bottles of it sitting on the vanity unit in her room. The royals aren't allowed to endorse brands or products, but that was a real nod of approval. After that, when Meghan moved in to Kensington Palace to live with Harry, he was tasked with building her shoe rack, or I should say, a walk-in shoe room! One day, when he was working on it, he asked Antonella [Fresolone, the Cambridge's Italian housekeeper] whether she thought Meghan might like to sample the oil too, at which point Antonella further revealed that Kate had already given some to Meghan.'

With a whole world of cosmetics and skincare available to them, it says a lot that both the Duchess of Cambridge and the Duchess of Sussex have developed a loyalty to a single bottle of oil. Supplies are, according to Aalam, regularly replenished in the royal household.

So, what’s all the fuss about? Blended with 14 plant-based oils, it will no doubt appeal to Meghan's interest in natural ingredients. Caribbean coral extract doses the formula up with powerful anti-inflammatory properties, a soothing antidote to both post-pregnancy and post-holiday-in-Mustique skin. Then, there’s lavender herb oil, neroli and geranium flower, which combine for a calming scent that will help to encourage sleep. For Aalam, it's the inclusion of pomegranate oil that really sets it apart from the rest. 'I really think pomegranate oil goes under the radar, it should be lauded as the next wonder ingredient. It's the only oil to boast serious quantities of omega 5. I use one drop during the day and just pat it onto my face right before I apply my makeup, and at night I use however much I feel my skin needs on the day'.

The oil is so good that it brings with it a real loyalty to the product. There's a reason the Duchesses go back to it

How does Aalam feel about the royal connection? 'It's obviously a real compliment, and it really helped to launch the brand in the US. American's are obsessed with Kate over there, way more than with Meghan interestingly. But I do think the oil is so good that it brings with it a real loyalty to the product. There's a reason the Duchesses go back to it. Likewise, people will now buy into the oil purely because of the royal hype, but continue to buy it and come back to it time after time, that speaks for itself.'

Now carrying the unofficial royal seal of approval, the popularity of this potent oil will no doubt rocket after its launch into Harvey Nichols, so snap some up while you can. There's even a new cleanser that has been thrown into the mix (Beuti Skincare Pomegranate Glow Enzyme Cleanser, £55). Will this be the next addition to the royal vanity units?

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