Winnie Johnson's 12-year-old son was murdered by Ian Brady and Myra Hindley in 1964. But his body was never found. Now nearing 80, she tells Melanie McFadyean why she never gave up the search for him and why time is running out

The images are iconic – those unforgettable black-and-white mugshots of Moors Murderers Myra Hindley and Ian Brady. Less familiar is a haunting snapshot of one of their victims, Keith Bennett. He wears wire-framed spectacles and is smiling with the mischief and innocence of childhood. Keith disappeared four days after his 12th birthday in June 1964 and is the only child Brady and Hindley killed whose body has never been found.

Keith's mother, Winnie Johnson, sits on the sofa in her living room in Longsight, Manchester, with that image of Keith in a frame above her. A sampler with his face screened on to it accompanied by a poem hangs on another wall. "From that day to this / I pray both day and night / That I will find my Keith / And lay his soul to rest."

You wonder if she can bear to be asked yet again about her missing murdered child. Does she mind being asked about Keith? With her characteristic, surprising flashes of good humour, she replies, "No! Do I heck! I'd rather people talked to me about Keith than look at me and stare at me – I can't stand that. It makes me feel better talking about him."

Diagnosed with cancer a year ago and nearing 80, Winnie is desperate to find Keith's body before she dies. Maybe then she will find the peace that has eluded her for nearly 50 years. The last official police search, which was reinstated in 2003, ended two years ago but Brady, she is convinced, knows where Keith's body is. Winnie's last hope resides with him.

She has written to him several times. A few months ago she wrote again and sent him a DVD telling him about her cancer. He hasn't replied but she shows me a letter from him, received in 2005. There is no remorse, no clue about Keith's body, just complaints about his situation at Ashworth hospital and idiotic notions of political conspiracies against him. Brady's self-obsession is repulsive. And despite saying in 2006 that he had "clarity" about where he buried Keith, this came to nothing. In 2009, he wrote to Winnie again saying the police had "bungled the search" and added, "this is my last word on the matter". Perhaps it's not so much his last word as his last sick bit of power, his last dirty secret. Or perhaps, Winnie suspects, it's not his last secret, maybe there are more bodies and finding Keith's will lead to them.

Winnie also wrote to Hindley in 2002 and said at the time: "I begged [her] to tell me where Keith's grave was, but in my heart I knew she was a wicked sadist who would never tell and would take her terrible secret to the grave."

Despite agreeing to help locate Keith's body, Hindley failed.

As Keith's mother, Winnie is most in the public eye but Keith's brother Alan searched the moors for years with his siblings and volunteers, and he, too, corresponded with Brady and Hindley to no avail. He has set up a website dedicated to his brother on which he touchingly writes: "Keith … was an ordinary, uncomplicated child, with his head in the clouds … He lived for the natural world and animals … Keith was … one of life's more sensitive souls."

When Keith disappeared, he was on his way to join Alan and his other siblings at their grandmother's house nearby. Although old enough to make his own way, he was short sighted and had broken his glasses the day before, so Winnie made sure he got safely across Stockport Road. Heavily pregnant with her fifth child, Winnie went on to her weekly bingo session. She never saw Keith again.

Hindley was nearby, driving a Mini Traveller, Brady in the back. She stopped the car and asked Keith to help her carry some boxes. Brady then told Keith to get in the back with him, saying they were going to find a lost glove. Once on the moors, Hindley watched Brady set off with Keith. She claimed she didn't see what happened next. When Brady returned, he said he had raped and strangled Keith and taken a photograph.

Even though this is a matter of public record, Winnie has avoided the details. She knows he was raped but the police have never told her everything. Sometimes she thinks it's best; other times she thinks it might be better to know. "I did and I didn't want to know. I asked them once and they wouldn't tell me. I don't want to see the photos. It would break my heart – it would kill me."

In 1966 Brady and Hindley were jailed for life for the murders of 12-year-old John Kilbride, Lesley Ann Downey, 10, and 17-year-old Edward Evans. The fear was that they had got Keith and Pauline Reade but there was nothing conclusive.

But not long after his disappearance, Winnie knew Keith was dead. "I'd had Joey and was breastfeeding him. I heard a child's voice behind me saying, 'Mam, I'm at the back of you.' It was Keith, in spirit. When my husband Jimmy came in, he said 'You look like you've seen a ghost.' I said, 'I've not seen one but I've heard one. I'll never see Keith alive again.' He's around me all the time. I find it comforting. Sometimes I find myself talking to him. If they did find him I'd want to kiss him."

Given the heartbreak she suffers, the years of agony and her poor health, it's surprising how open, friendly and sometimes funny Winnie is. The day I met her, the film-maker John Coffey sat with her while she watched his documentary about her. At one point she wept and he comforted her. She recovered and cast Coffey an embarrassed, sidelong smile when on the film she says they should cut Brady's balls off and stuff them in his mouth. "You bugger, you left that in!" she says. He is about to reply and she says with a smile, "Oh, shurrup you!"

When she smiles you see a flash of the girl she was. She says she was always full of mischief. "I was at school in the war. My mates and I said let's wag it and go in the air-raid shelter. I was mischievous and used to get in loads of trouble. I wasn't interested in school, I wanted to get out and do something I shouldn't be doing."

Winnie loved dancing, and met Keith's father at a dance hall. She's vague on dates and details – asked how long she went out with him she says, "Jesus! Now you're asking me summat!" His name was Frederick Norman and his parents were French. Asked if he was handsome and dashing, she replies, "Was he heck!"

She was 19 when Keith was born and she came home to her mother from hospital crying: "My mother said, 'Now what the bloody hell's wrong?' I said, 'Mam, I hope the same doesn't happen to Keith as happened to Margaret.' When my younger sister Margaret was seven she ran past the fire and her dress caught alight. She died. I said what if something happens to Keith like it did to Margaret – and it did, in a different way."

Winnie had a second child, Sylvia, with Norman but things didn't work out. "I told him to bugger off one day because he was going out with different women behind my back. I was very angry."

He has never been in touch since.

She wasn't alone for long. "I met a lad at Moseley rubber works where I was working; he was the father of the next three – Alan, Ian and Margaret." When Winnie discovered he, too, went out with other women, she left him. Winnie and her five children lived with her mother, Gertrude, who helped look after them.

Being the single working mother of five children by two men can't have been easy in the 1950s. Winnie shrugs and chuckles. "At first when I was pregnant people criticised me but I said it's me that's having the baby, I'm going to keep it. I didn't give a damn; I said it's my own bloody life. I love kids, they keep you young. Having kids made me strong. My mother agreed with me, she said, 'Anybody comes near you, let me know – I'll give them a right mouthful.' My auntie from Newcastle came and said to my mam, 'You should put her out of the house'. My mother said, 'If you're going to criticise me, you'd better get out – she's my daughter and I'll do anything I can for her.' She left. I never spoke to her again."

Gertrude was always fiercely protective. One day, after Keith went missing, she and Winnie were walking along Stockport Road. "Someone came up to me and said, 'You're Keith's mother aren't you. They cut him up and gave him to the pigs.' I couldn't speak, all I could do was cry. My mam went mad. She went to hit the woman – she said, 'What kind of a person are you?'"

In 1963, the year before Keith disappeared, Winnie fell in love with Jimmy Johnson and married him. When Keith went missing, Jimmy was treated as a suspect and the strain threatened to destroy the family until Winnie confronted the police – Jimmy loved her kids like his own. As well as coping with this and as consumed with grief as she was, she tried to do her best for Sylvia, who was 11, Alan, eight, Ian, seven, Maggie, four, and Jim's 11-year-old daughter, Susan. "I looked after my children. I wouldn't let anything happen to them. They asked me all the time after Keith went, why has he gone? I said I don't know. They said when are you burying him and I said as soon as I can."

She kept going because she had to, but says: "I seemed to lose all faith in doing anything for the first five years, just didn't want to know. And now with my grandkids [she has 18], I'm frightened to death of anybody picking them up and taking them."

Winnie and Jim had three more children, Joey, David and Kenny, and brought up Jimmy's grandson, Tony. Tragically, Tony was shot dead, aged 22 in 1991, the same year that Jimmy died. You wonder how Winnie has survived so much tragedy.

At first it seemed strange that she should want to take us to the moors, travelling the route along the A635 that Brady and Hindley took with their victims. Since 1985 when Brady admitted that he had murdered Keith and Pauline Reade, Winnie has gone to Saddleworth Moor many times. She says she likes it there; she feels closer to Keith. As we reached the bleak moorland slopes, she points to Hollin Brown Knoll, a rocky outcrop where Pauline Reade's body was found, and to faceless patches of moorland where police unearthed the bodies of Lesley Ann Downey and John Kilbride. She directs the minicab driver to a layby a few miles further on towards the area where Brady is thought to have buried Keith.

Winnie stands looking across the desolate moorland, one hand on a fence post to which on a previous visit she had tied a blue teddy bear. On other posts are remnants of flowers and a wreath.

She is shivering but stoical. "He could be anywhere on these moors, such a vast area," she says. "The police have stopped searching. I just hope someone will spot his burial ground." On the way back she talks about how she has survived. "Once or twice I thought I was losing my mind and thought of suicide, but I thought I've got to carry on because I've got the other kids. It wouldn't be fair on them." She pauses. "What can you do?" It's a phrase she often repeats. "I've just got to live with it and bear my temper," she continues. But her mildness of manner belies the rage that never goes away. "I still feel very angry, as angry as I ever did. They should be tortured – do the same to them as they did to those kids."

Some people keep a dead or missing child's possessions, and leave their bedroom as it was the day the child vanished or died. Winnie didn't keep anything except Keith's broken glasses but it didn't make his absence any more bearable. "Keith is always on my mind because I've never found him. I think of him before he went missing. Like any kid he'd say, 'I'm not going to school.' I'd say, 'You are.' He came home dinner time and said,'Mam, I've broke my glasses. I said, 'You're not staying off school. Get back to school.' He broke them when he went swimming, he broke one lens. I said, 'Go back to school and wear them as they are. Tomorrow I'll take them to the clinic."

But she never did because on that day Brady and Hindley murdered her boy.

• Dear Mr Brady, a documentary about Winnie Johnson by John Coffey, will be shown on Channel 4 in the spring

{loadposition user38} source: http://www.guardian.co.uk/lifeandstyle/2012/jan/07/winnie-johnson-keith-bennett-moors-murders

source: http://www.europerank.com/lifestyle/lifestyle/58988-where-s-my-keith