The mother of a toddler who disappeared more than 30 years ago is anxiously awaiting the results of a DNA test on a man claiming to be her long-lost son. Ben Needham was just 21 months old when he disappeared on the Greek island of Kos in 1991.

The toddler was last seen playing outside a derelict farmhouse on the island and his parents have searched the world for their boy, the Manchester Evening News reports.

As the 33rd anniversary of Ben’s disappearance approaches on Wednesday 24 July, his mother Kerry is waiting to hear if a stranger could be her son – for the third time this year. A man from Denmark claims his grandparents told him he was taken from Kos and insists his parents do not deny the claims.

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The man says he was hidden for years and remembers going to a market 25 years ago and someone shouting “Ben” at him. He claims he was held in a caravan at the time, the Mirror reports.

But Kerry, 51, from Sheffield, says she can never get her hopes up, having been in this situation several times before. She said: “This man is searching for his real family and he has given Danish police a sample of his DNA, which South Yorkshire Police are trying to obtain through Interpol to compare with Ben’s.”

The stranger’s DNA samples will be compared to a blood sample taken when Ben was born at Boston Hospital in Lincolnshire, for the routine Guthrie heel prick test. The mother also said she feels the pain of Jay Slater’s family and warns trolls about the further harm they are causing.

The 19-year-old was found dead in a steep gorge in Tenerife on July 16 after a months-long search for him. After watching them follow in her footsteps, Kerry said her “heart is completely with them”.

She added: “The only thing I can say to give them some comfort is that it’s better to know, because living year after year without knowing is torture. I feel their pain.”

She hit back at trolls who had mocked Jay’s mother Debbie Duncan, saying: “People have been so cruel. You have no idea the heartache and pain it causes.

“The trolling has to stop.” But she said the £66,000 raised for the family at least shows there are still kind-hearted people out there.

And about her son’s “sightings,” she said: “In 33 years we’ve had hundreds of alleged sightings, most of which we investigated ourselves in the earlier years.

“We’ve had DNA taken from people in Greece, Turkey, Germany and one each in Florida and Australia. But at least South Yorkshire Police are trying to give me some answers and I can’t praise them enough.”

Police theorize that Ben may have died in a backhoe accident after a witness came forward. But blood found at the scene in 2016 turned out not to be Ben’s, and the witness refuses to speak to police again.

Kerry said: “You can’t close an investigation without something to fall back on and the claims of a man who now won’t talk.” She added: “I can’t believe it’s been 33 years and he’ll be 35 in October.

“My mother is 72 and my father is 76. I don’t want anything to happen to my parents without them knowing.”

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