Lettice played for Prince Charles at Buckingham Palace several years ago – and the 24-year-old has also been approached by bosses of Made in Chelsea to appear in the show.
Leslie said: "I’ve never really considered myself posh, it’s mainly about talent", but the 24-year-old also admitted that she is a party girl, who was hungover during her audition.
Leslie Rowbotham performs on Britain's Got Talent
The violinist also has big ambitions, dreaming of being as big as popstar Beyonce.
"It was so much fun. I do like to party and going to pubs so I was a little hungover at the audition. I want to be as big as Beyonce, have my own tour and merchandise", she said.
But the success of Britain’s Got Talent won’t slow Lettice down, as she said: "There are plenty of people around me who will probably encourage me to have a few more early nights. But I’ve always been a party animal and I’ve plenty of energy."
Lettice studied at the Purcell School of Music in Hertfordshire and then later at the Royal College of Music. She has toured with Olly Murs and performed at Vladimir Putin’s daughter’s wedding.
After her audition Simon Cowell said: "Lettice, not only are you brilliant, you have a fantastic personality as well, you are one of the people I am going to remember coming away from this."
The young musician’s mother is also an artist - whose artwork the royal family collect.
Sherree Valentine Daines is an impressionist painter and her artwork can sell for up to £10,000. Several pieces of her artwork have been shown at the Tate and the Barbican in London.