The jewellery item, which contains a rare blue diamond, was purchased for the legendary child star by her father in 1940 for $7,210 (£4,976).

Bosses at Sotheby's auction house expect the diamond ring, known as the 'Fancy Deep Blue', to sell for between $25 million and $35 million (£24.2 million) when it is auctioned in New York City on 19 April (16).

Shirley, whose performances in films like The Littlest Rebel made her one of Hollywood's most popular stars in the 1930s, died in 2014 at the age of 85.

Since her death, the actress' family have auctioned off a number of pieces of memorabilia from her career, including the dress she wore to the 1935 Academy Awards.

After retiring from acting in 1949, the former actress entered politics, serving as the U.S. ambassador to Czechoslovakia and Ghana.