Hayley Mills was devastated that her Juvenile Oscar was stolen.
The 77-year-old English actress won the award for her performance as the titular character in 1960 Disney movie 'Pollyanna' when she was aged 14, though was deprived of the prize shortly after receiving it in 1961.
Hayley couldn't get a replacement because the Academy made the decision to present child stars with the full-size statuette.
In an interview with Closer US, she said: "Unfortunately, some not very nice person stole it. I was never going to get it back because when they gave me mine in 1961, they broke the mould. Literally.
"From 1962 on, the next child to get an Oscar got a big, full-sized one. When I lost mine, I was desperate and I kept thinking it must turn up."
Despite winning the prestigious award, her parents didn't let her attend the ceremony in an attempt to try and keep her life as normal as possible, a decision Hayley now respects.
She explained: "I think my parents thought it was important that things were kept in proportion.
"I totally understand why they decided this is just too much of a good thing. I was only 14, and they really didn't want me to get too full of myself. So I didn't go to the ceremony. I was asleep at school."
Having had so much glory at such a young age, the actress admitted that she felt guilty about her success.
Hayley said: "It was all tied up with wondering if it had all been a terrible mistake because I hadn't done anything to earn it. I hadn’t gone to drama school. I hadn’t done endless auditions and been rejected and failed.
"I was just a child being a child and suddenly this gift was given to me. But I wouldn’t want you to think that I was beating my breast the entire time because, certainly in the early days, I loved what I was doing. I had a wonderful time."
As well as her success in 'Pollyanna', Haley went on to star in 1961 film 'The Parent Trap' for Disney, and got the opportunity to meet Walt Disney in person.
When asked what the iconic animator-and-producer was like, she said: "He was a very genuine human being, a very real, warm, interested, curious, kind human being.
"He genuinely loved children. He had a lovely sense of humour. He was really easy to talk to because he listened."
