Lady Kitty Spencer celebrates Viscountess Weymouth's birthday in Elizabethan ballgown

By Ainhoa Barcelona

Lady Kitty Spencer travelled back in time for her friend Viscountess Weymouth's thirtieth birthday party. Princess Diana's 25-year-old niece stuck to the dress code in a traditional voluminous ballgown for the Elizabethan-themed bash at Longleat.

The pretty blonde posed at the bottom of a staircase with her boyfriend Niccolò Barattieri di San Pietro and captioned the magnificent shot on Instagram: "Thugs at the disco."

She also shared a sweet close-up photo of the pair on the dancefloor. "My King #elizabethandisco #1554," Kitty called her Italian beau.

TAP TO VIEW GALLERY Lady Kitty Spencer attended with her boyfriend Niccolo

Kitty was just one of the privileged guests to attend Viscountess Weymouth's lavish bash at Longleat estate. The birthday girl, born Emma McQuiston, and her husband Viscount Weymouth threw open the doors to their stately home to host an Elizabethan-themed party. Guests were greeted by the projection of a sparkling disco ball on the facade of the building as they arrived.

Princess Diana's niece called her Italian beau "her King"

Leading lady Emma looked ravishing in a white leotard-style dress that she topped off with a glittering tiara. She posed with model Eunice Olumide and American rapper Eve in one Instagram photo.

Blogger Rosie, known as The Londoner, was also in attendance and shared a picture of Emma's first outfit of the night – a burgundy, tiered ballgown.

Viscountess Weymouth invited rapper Eve to her birthday party

Emma married her Viscount husband Ceawlin Thynn at Longleat in June 2013. The former TV chef gave birth to the couple's son The Hon. John Thynn in October the following year.

Speaking exclusively to Hello! about the birth, Emma explained how her baby boy brought new life to Longleat.

"It feels like a renaissance," she said. "It's always been vibrant here – there's always been something exciting going on – but it's a new generation, a new dynamic. It's a very exciting time."

Adding that the birth was "incredible," Emma said: "Ceawlin held him first and then put him on my chest. I was just like, 'Wow.' You forget everything, nothing else matters once you have a baby.

"It's made our relationship stronger because we've had something serious to cope with and we both love the baby so much, this person we've made. It's extraordinary how nature works. Mind-blowing."

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