Ben Needham: Mother's book to raise missing boy profile 31 December 2012 Last updated at 15:29 A mother whose son disappeared while on holiday 21 years ago has said she hopes a book about her ordeal will help bring him home. Ben Needham, from Sheffield, went missing during a family holiday on the island of Kos in 1991 when he was 21 months old. Kerry Needham has always maintained her son is alive and was probably abducted. She described writing the book as "very traumatic" but said she hoped it would help raise the profile of her case. Ms Needham added: "It was heart-wrenching to live the last 21 years of my life day by day and put it into perspective. You're reliving it and that was really difficult to do but I think it will be worth it and it will raise the publicity about Ben. Search for remains In October, police began a a major new search for Ben's remains near the family's former farmhouse on Kos but nothing was found. Ms Needham said flying out to the island for the search was "one of the hardest things I've ever done." "Just the thought of being on that island while digging up that ground was so traumatic that even now I'm not over it." she said. It knocked me back really bad but it had a positive outcome so I'm grateful for that. Ms Needham said they were now working on a new lead of a photo of a mystery boy who resembles Ben. She was making an appeal on a Greek TV programme when a viewer contacted the show with the photo. The picture is said to have been taken in the Corinthia area of Greece sometime in 1995 when Ben would have been five or six. She said: "We're working all day and night trying to follow up lines of inquiry on that." Ms Needham added: "We don't want to raise our hopes too much because it's devastating if it turns out not to be Ben and I'm crucified all over again." The book is due to be released next year.