Lynch made her movie debut as Luna Lovegood in the fifth Potter film, Harry Potter and the Order of the Phoenix, in 2007, and admits she got the role after responding to a casting call on fansite MuggleNet in January, 2006.

Producers of Fantastic Beasts have turned to the same website in search of girls aged eight to 12 for the role of Modesty in the film adaptation of author J.K. Rowling's 2001 book.

Lynch took to her Facebook page on Monday (13Jul15) to encourage diehard Potter fans like her to take a chance and audition for a role that could change their lives.

She wrote, "I was shy, awkward, too-sensitive-for-this-industry, had not one professional credit to my name and I faced many a raised eyebrow and skeptical comment when voicing my dream to audition to family and friends. I only went out of love for the books and a fierce desire to tell Luna's story the right way. But I was by all means, NOT ready or trained to audition for a role in a mega movie franchise.

"There was a lot of luck at play in the beginnings stages (like not being born a boy and being the right age and nationality) but when it came down to making decisions I think the sole reason I got it (the part) was because of love. I'm sure there were better, prettier, more established actresses who went for it but I don't think any of them loved Luna as much as I do."

She continued, "With that in mind, I just want to encourage any girls out there who are tempted to go for this but feel like it's impossible or bigger than you are, to put all those alleged obstacles out of your mind and just go as you, nothing more, nothing less... Also, some personal advice, if your mum tries to talk you out of auditioning for this then go sweet-talk your dad. good luck anyone who's auditioning and enjoy it!!"

Oscar winner Eddie Redmayne has already been cast in the film, which is set 70 years before the events of the Potter series and centres on the adventures of fictitious author Newt Scamander.

Filmmaker David Yates, who directed the final four instalments of the Potter franchise, will direct the project.