How Prince Louis caused a 400 percent sales boom

Princes and Princesses don't drink just any old baby milk formula, and one lucky British-made brand is experiencing a boom after it was revealed that it is the one used to feed Prince Louis, 11 months.

Kendal Nutricare was reportedly contacted last November by royal nanny Maria Teresa Turrion Borrallo.

Now, Kendal Nutricare is experiencing a boom thanks to the fact it is British-made and being used by the royal family.

Borrallo has been nanny to all three of the children of the Duke and Duchess of Cambridge since the birth of Prince George in 2013, then Princess Charlotte, 3, and now Prince Louis.

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The Telegraph in the UK reports that it was at the Commonwealth Heads of Government Meeting (CHOGM) in London that the Norland-trained nanny first heard of the full-cream baby formula, made using 100 percent British ingredients.

George and Charlotte were breastfed and then weaned onto Aptamil, however by the time Louis was being weaned, the family made the decision to switch to Kendal Nutricare.

The Cambridges were so happy with the product that Kate's sister Pippa Matthews - who gave birth to baby Arthur in October - also uses it.

Susie Wilshire, the maternity nurse who looked after George and Amal Clooney's twins Ella and Alexander, 22, is also a fan of the product.

Thanks to both the royal and celebrity seals of approval, the company has grown by 400 per cent.

The company had originally sent the formula to the Royal Family for free, however it was sent back along with a note explaining they couldn't accept free products and would purchase it.

** A previous version of this article contained inaccurate information about Aptamil. It has since been updated.