Linda Ann Smith was a happy child who was 4ft 6ins tall, with blue eyes and light brown hair. Although her family say she could be a little shy she was a warm and friendly girl, and would speak to everybody she met. Her engaging personality led to many knowing her as Little Miss Friendly.

East Anglian Daily Times: Linda's sisters Fiona, Petra, Jane and SheenaLinda's sisters Fiona, Petra, Jane and Sheena (Image: Archant)

At the time Linda was the eldest of six children born to Robert and Patricia Smith. Linda adored her rabbit and the Fluffy, the family cat.

East Anglian Daily Times: The incident is the oldest unsolved murder that is on Suffolk Constabulary's cold case reviewsThe incident is the oldest unsolved murder that is on Suffolk Constabulary's cold case reviews (Image: Archant)

She was interested in wildlife, enjoyed reading, and collected old tobacco tins. After attending Earls Colne Primary School she went to Halstead Secondary Modern.

On Monday, January 16, 1961, she returned to her Earls Colne home after school before going to her great grandmother Emily Sharman’s home in the village.

Sometime after 4.30pm Linda left with a 10 shilling note to buy a magazine for Mrs Sharman from Hughes, the newsagent’s in the High Street, around five minutes walk away.

There were four confirmed sightings by those who knew Linda between then and around 5.10pm. She never went into the newsagent’s, despite being seen looking in the shop’s window by her friend Margaret Mattin, aged 12.

When Linda did not return to her great grandmother’s home police were called. In the days following her disappearance hundreds of people joined search parties to scour fields in an effort to find her.

However, Linda’s clothed body – which was missing a size one, black, right lace-up shoe – was found in a field beside Stackwood Road, a narrow lane at Polstead, near Hadleigh, by Harold Richardson. The 72-year-old retired farm labourer had been returning home from a walk at around 3pm on Friday, January 20.

Linda’s overcoat still contained the 10 shilling note in her purse.

Mr Richardson had seen what he said were “thousands of pigeons” on a stubble field on Evans Heath Farm.

Speaking at the time he said: “I went into the field and then saw on the headland, by the hedge 15 yards away, what I thought was a bundle of clothes.

“I went up and got the shock of my life. I could see the poor little thing (Linda) lying alongside the hedge with her hands and legs stretched out.

“I pulled back the hood of the school mac and could see it was the little girl Linda Smith. We had only been talking about her at the Butchers Arms (at Nayland) at dinner time.”

An expert said she died on the Monday she went missing or the following day.

A subsequent inquest heard a red substance, believed to be paint, and traces of flour were found on Linda. These were matched to the clothing of a man spoken to during the inquiry. His car also contained the traces of the red substance. However, he was never arrested and police only ever described him as a potential witness.

Eight shoe impressions were found where Linda was dumped, five facing her body, along with a reindeer mint – a sweet sold in Co-op stores.

After Linda was found her five siblings, including brothers Robin, now 59, and Melvin, now 53, were sent away for several weeks to shield them from what had gone on.

As with many of those brought up in the 1930s and 1940s Linda’s mother Pat bore the loss with stoicism despite her despair.

Even now the 84-year-old finds it hard to publicly articulate the depth of her pain.

Pat said: “I just had to pull myself together because of the rest of the kids. It broke my heart. I was just numb. I had the feeling I would never see her again. I felt angry about why it should have happened to her.”

Recalling the day Linda left her home to go to her great grandmother’s, Pat said: “Linda was a quiet, happy girl. She just said I’m going to do Nana’s papers.”

Linda’s eldest sister Sheena said Linda’s death also took a heavy toll on her father, Bob, who died in 1984.

“I think he was absolutely devastated. He had gone out searching for Linda with the search parties.”

Even now there is no escape from the trauma of the past for Pat.

When television and newspaper appeals are put out for missing children her thoughts immediately return to Linda.

She said: “When I see something like it happens on TV it brings it back, but I keep the emotions to myself.

“I just know how the other parents must feel when their children go missing.”