Princess Charlotte's John Lewis cardigan from birthday photo sells out

In the snapshot, the young royal is wearing the cardigan and sporting a navy clip in her hair

John Lewis confirmed that the clothing item sold out online shortly after the photograph was published (HRH The Duchess of Cambridge via Getty Images)

A knitted yellow John Lewis cardigan adorned with pictures of sheep has sold out after Princess Charlotte was photographed wearing the item, prompting a surge in demand from British parents wanting to dress their offspring like the young royal.

Royal fans were treated to a new portrait of the Princess on Monday, taken by her mother the Duchess of Cambridge, to mark Charlotte’s second birthday on 2 May.

In the snapshot, the young royal is wearing the cardigan and sporting a navy clip in her hair.

John Lewis confirmed that the clothing item sold out online shortly after the photograph was published, although a coordinating prink dress, selling for £10 on the John Lewis’ website, was still available on Tuesday morning.

At the time of writing, the coveted yellow cardigan was also available on eBay for £18.

It is not the first time Princess Charlotte has proved a trend-setter for children’s fashion.

Last year, a photograph of Charlotte on the occasion of her first birthday sparked fierce demand for a cream cashmere cardigan made by a brand called Olivier Baby & Kids.

Experts at Brand Finance, a company that specialise in brand valuation have previously predicted that Princess Charlotte will be worth more than £3bn to the UK economy across her lifetime.

Her older brother Prince George, is expected to bring in £2.4bn.