Prince and Princess of Wales share sweet moment as they attend the Earthshot Prize in Boston

The Prince and Princess of Wales shared a very sweet moment as they were seated at the glitzy Earthshot Prize ceremony in Boston last night.

The royal couple put on a rare public display of affection earlier in the night, briefly holding hands as they walked into the MGM Music Hall at Fenway for the event – which has been described as William’s ‘Super Bowl moment’.

Such displays are very unusual for the couple. They typically keep a slight distance at public engagements – as they did in the photo call for the eco-friendly awards.

But they later shared an intimate moment as they were seated inside the venue, William placing his hand on his wife’s back as they leaned together to talk quietly.

Kate, 40, certainly pulled out all the stops on Friday – taking a break from her normally-reserved sense of style in order to steal the spotlight in the eye-popping number.

In keeping with the theme of the evening, the Princess chose to don a rented design from a brand called Solace London, which the royal got from online designer rental platform HURR – which charges between £74 and £194 to loan the gown. 

However, while Kate’s borrowed garment was a far cry cheaper than the high-fashion pieces she normally sports, she added plenty of bling to her look in the form of a stunning diamond-and-emerald choker that once belonged to her late mother-in-law Princess Diana. 

The dazzling art deco choker – which is believed to be worth more than £12 million – was gifted to Diana by the Queen, who herself inherited it from her grandmother Queen Mary. 

Diana wore the choker on a number of occasions, even pairing it with a green off-the-shoulder gown, just like Kate, when she attended a glittering event in London back in 1993. 

However, the choker necklace is perhaps most famous for being worn by Diana on her head during her and then-Prince Charles’ tour of Australia in 1985. 

At the time, images emerged of the then-Prince and Princess of Wales dancing at a gala in Melbourne – in which Diana could be seen wearing the pricey piece of jewelry around her forehead like a headband. 

It was later revealed that the fashion-forward moment happened purely by chance, after the Princess got the necklace stuck on her head while putting it on – only to like the style so much, she chose to keep it that way for the rest of the evening. 

Kate added some more sparkle to the look with a pair of matching £9,220 Asprey diamond-emerald earrings, which she is understood to have recycled from her own collection, in keeping with the theme of the sustainable event. 

Similarly, the Princess turned to her own closet when it came to her shoes – a pair of dazzling Gianvito Rossi heels. 

Having encouraged guests at the Earthshot gala to wear vintage, re-used, or second-hand clothing in order to fit the event’s sustainable theme, Kate set a shining example by sporting the designer shoes, which she has worn on a few occasions in the past – including at a reception in the Bahamas during the Waleses’ Caribbean tour in March of this year.

She had her long brunette locks styled in her signature loose waves, however she pulled her hair back behind her ears in order to let the off-the-shoulder design, and her dazzling jewels, to really shine.

This evening’s event marks the second time that Kate has chosen to wear jewelry belonging to Diana; upon her and William’s arrival in the US on Wednesday, the Princess sported some diamond-and-sapphire earrings that her late mother-in-law once owned. 

Meanwhile, William put on a dapper display in a black tuxedo, keeping things classic with a dark navy velvet jacket and a black bow tie, while also sporting an Omega watch.

The Prince and Princess of Wales were given a Hollywood-style welcome as they arrived at the event, with cheering crowds offering up cries of support as they exited their hybrid Range Rover – a vehicle that was specially chosen to fit the eco-friendly focus of their trip. 

Kate and Wills made their way down the ‘green carpet’, pausing a few times to speak to other guests, before making their way into the venue, where they were greeted with a standing ovation from the other attendees. 

Once inside, they were joined by Earthshot council members, John Kerry, Ms Naomi Yamazaki, Hindou Ibrahim and Indra Nooyi, as well as the program’s CEO Hannah Jones.