Months after he went missing, Bobby was returned to his family. But something wasn't right.

In August 1912, Lessie and Percy Dunbar of Opelousas, Louisiana, took their four-year-old son, Bobby, on a fishing trip.

It was during that trip to nearby Swayze Lake that little Bobby Dunbar disappeared.

After an eight month search authorities found a boy in Mississippi who appeared to match Bobby’s description.

The boy had been travelling with William Cantwell Walters, a handyman who roamed around the country, tuning and repairing wealthy people’s pianos and organs.

Walters was immediately arrested for kidnapping and the boy was reunited with his parents.

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According to newspaper reports at the time, Lessie and Percy may not have initially recognised the boy.

While one newspaper reported that Bobby immediately shouted out “Mother” upon seeing Lessie, another said the boy only cried. Lessie was also quoted as saying she didn’t recognise him.

There were also contradictions in the accounts of the boy being united with his younger brother, Alonzo. One paper reported that Bobby didn’t appear to recognise his own brother, while another wrote that he recognised him instantly, called him by name and kissed him.

The next day, Lessie bathed the boy and said she could positively identify him by his moles and scars, and she was now certain he was her son.

However, Walters, the man accused of kidnapping Bobby, had a different story to tell.

He told the authorities the boy wasn’t Bobby Dunbar, that his name was Charles Bruce Anderson, generally referred to as Bruce, the son of an unmarried field worker who was employed by his family.

The field worker was named Julia Anderson and Walters said she had willingly given him custody of the boy because she couldn’t look after him.

Anderson backed up Walters story… sort of. She said she had given Walters permission to take Bruce on what was supposed to be a two day trip to visit some of Walters’ relatives and that Walter just never returned him.

The Dunbars, Anderson and Walters ended up in a court battle. The court sided with the Dunbars and Walters was sentenced to time in jail for kidnapping.

After the trail Anderson relocated to Poplarville, where she built a new life for herself – eventually marrying and having seven children with her new husband.

However, her descendants said she never stopped talking about the son she had lost.

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Anderson and Walters maintained the boy was Bruce Anderson for the rest of their lives. And the boy went to his grave believing he was Bobby Dunbar.

Then in the early 2000s one of Bobby’s granddaughters, Margaret Dunbar Cutright started looking into her family’s history.

All her life she was told her grandfather was kidnapped as a child and reunited with his parents eight months later.

When she began poring over newspaper reports from the time she realised there could be more to the story.

The rest of her family considered themselves to be proud descendants of Bobby Dunbar and they wanted Margaret to drop her investigation.

But she didn’t. First she interviewed Julia Anderson’s children and then she thoroughly read through the notes and evidence presented by Walters’s defense attorney for his kidnapping trial and appeal.

She became convinced Bobby Dunbar wasn’t Bobby Dunbar after all.

Then in 2004, after an Associated Press reporter became interested in the story Bob Dunbar Jr, one of Bobby’s sons reluctantly agreed to a DNA test.

The results proved that Bobby Dunbar was not actually a Dunbar. He was, in fact, Bruce Anderson.

Lessie and Percy Dunbar were either so distraught over the loss of their son that they truly believed Bruce was Bobby, or as Anderson always believed, they just decided to keep the boy even though they knew he wasn’t their son.

To this day no one knows what happened to the real Bobby Dunbar. Margaret believes he most likely fell into the Swayze Lake during the fishing trip and was eaten by an alligator.

And while her findings brought vindication to the Anderson and Walters families, it tore her own family apart.

You can hear about Margaret’s – and Bobby’s – story on the This American Life podcast.

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