Dr. Raymond Moody sat at his 74-year-old mother's deathbed.

After a late diagnosis of non-Hodgkin lymphoma, doctors said the disease had already progressed so far that chemotherapy would have little effect and that she had less than two weeks to live.

Shocked, family rallied to say their goodbyes - but as she died peacefully, her loved ones could never have imagined that they would be a part of what Moody calls a shared death experience.

The phenomenon, claims Moody - a renowned philosopher and psychiatrist - provides an answer to the biggest mystery of life: What happens when we die?

'Mom had been the pillar of our family, and now we needed to be her pillar,' he writes in his book, Proof of Life after Life.

'We all gathered in Macon, Georgia, where she lived and was now hospitalized, to be with her during her final days. There were six of us - siblings and in-laws - and we all worked hard to provide her with as much comfort and love as we possibly could.'

On what was to be her last day, they were all by her bedside when it was clear the end was just minutes away.

'We all held hands in a circle around her bed and waited for her to pass,' he writes. 'As we did, the room suddenly changed shape - for all of us.'

Dr Moody and his family were gathered around his mother's hospital bed when they had a shared death experience (stock photo)

The phenomenon, says Moody (left) - a renowned philosopher and psychiatrist - provided what he believes is proof of the biggest mystery of life: what happens when we die?

'For me, it became the shape of an hourglass,' he says. 'Four of the six of us felt as though we were being lifted off the ground in a glass elevator. I felt a strong pull upward, as did two of the other five.'

Several family members say they also saw their father - who had died a year and a half earlier - standing at the end of the bed.

'And when I say "saw him", I mean we saw him as solid as though he were standing in front of us in the flesh.'

All those present reported that the room took on a 'soft and fuzzy texture and was opaque like the light in a swimming pool at night.'

Moody's brother-in-law, a Methodist minister, described it as feeling 'like I left my physical body and went into another plane with her. It was like nothing that has ever happened to me.'

After Moody's mother died, they all compared notes and agreed they had accompanied their mother 'at least part-way to heaven' - sharing some of her death experience along the way.

But, rather than being terrifying or even unsettling, he says, it was one of the happiest days of their lives.

Moody writes that the 'communication from another world' had made the blanket of sadness 'leave the room and be replaced with great joy.'

Moody is no stranger to the supernatural. A former forensic psychiatrist who worked in a maximum-security state hospital, he was not brought up to be religious. He had even thought afterlife talk was a joke.

But his studies of thousands of people who claimed to have died and 'seen' what lies beyond led him to popularize the term 'near death experience' (NDE) and convinced him there is life after death.

In one particularly vivid account, a woman Dr Moody calls Betsy found herself at one end of a tunnel, and her dying mother-in-law at the other

'Another thing people say is that they leave their bodies… and accompany the dying person into the afterlife'

However, NDEs alone are not definitive proof of an afterlife, he says, because they are subjective and unable to be verified.

Which is why, when he heard of a shared death experience (SDE) - first from a professor at medical school who witnessed the death of her own mother - Moody was understandably curious. 

Could SDEs be the missing link of objectivity, proving the existence of an afterlife?

He had been studying the phenomenon for some time before it actually happened to him, and claims SDEs are much more common than people realize.

'The things that I hear most commonly are this idea of the room filling with light and becoming aware of the presence of, or apparitions of, the dying person's deceased loved ones coming into the room,' he tells the Daily Mail.

'Another thing people say is that they leave their bodies… and accompany the dying person into the afterlife.'

Sometimes, he adds, it takes the form of seeing a cloud rise from the body and hovering before disappearing.

This was the case with Little Women author Louisa May Alcott, who recorded the death of her sister Elizabeth in her diary. 

She wrote: 'A curious thing happened, and I will tell it here, for Doctor G [Dr. Christian Geist of Boston] said it was a fact. 

'A few moments after the last breath came, as Mother and I sat silently watching the shadow fall over the dear little face, I saw a light mist rise from the body, and float up and vanish in the air. 

'Mother's eyes followed mine, and when I said, 'What did you see?' she described the same light mist. 

'Doctor G said it was the life departing visibly.'

Little Women (pictured) author Louisa May Alcott  recorded the death of her sister Elizabeth in her diary

They all reported that the room took on a 'soft and fuzzy texture and was opaque like the light in a swimming pool at night'

In one particularly vivid account, a woman Moody calls Betsy was caring for both her husband, who had dementia, and his mother, who was dying in a local hospital.

One night, he says, as Betsy sat with her mother-in-law, she found herself in a tunnel that had suddenly appeared.

'At one end of the tunnel stood a much younger looking version of her mother-in-law seemingly beckoning to Betsy and saying in a clear and strong voice, 'Come on, it's great in here.'

She refused the invitation, reasoning that she had to stick around and care for her sick husband.

'Suddenly,' he says, 'Betsy realized that her mother-in-law was not beckoning to her but to [her husband] Bob, who was standing behind Betsy also in the tunnel. Bob also looked younger and healthier. He was noticeably happy as he looked at this healthy version of his mother.'

Soon after, the tunnel closed, and her mother-in-law died. One month later, Bob suffered a respiratory infection and died, too.

'For years, I just assumed this had to only happen with people who were very intimate with the patient,' he tells the Daily Mail.

'For example, the first two cases I heard happened to be women in their 40s who had lost their teenage sons.'

But then, an emergency room doctor got in touch with him to describe witnessing the 'life review' of a dying patient he'd never met before.

Other medical professionals also reported seeing patients lightly glowing as they died.

'People may see a halo or other light shining around the head of the dying, or they see mist or shapes leaving the body. In some cases, these shapes may assume a human form.'

At other times, multiple people have claimed they heard music from a loved one's deathbed.

'One of the most famous cases occurred in the 17th Century at the deathbed of German writer Johann Wolfgang von Goethe, when five people heard inexplicable spherical music in his house yet could not trace its origin,' Moody explained.

'In another astonishing case, a deaf-mute person indicated he heard music, as did the bystanders at his deathbed, a recovery of senses that resembles blindsight - reports in which blind people claim to see during NDEs.'

Cynics say such experiences are optical illusions, or the result of extreme stress, and the imagination playing tricks on us. But, Moody says, the fact that many of these SDEs are witnessed by so many other people at the same time is compelling evidence that the soul survives the body.

Unfortunately, it's not something that can be forced or manufactured.

When asked if anyone could create the kind of environment that might enable them to share in their loved ones death, he said he'd never heard of such an experience.

'I don't know,' he answers. 'If somebody rehearsed how they're going to be, there would be a kind of self-consciousness to it.'

His advice is to allow it to be spontaneous.

'Shared death experiences make it clear that consciousness is not just a chemical reaction in the brain, separate from the spiritual,' he argues. 

'[They] are proof that near-death experiences are more than oxygen deprivation to the brain. 

'Bystanders to death can have the same transcendent experiences as those who are dying or who are retrieved from a close call with death. This new development - the aggressive study of shared death experiences - puts us at the frontier of the afterlife.'

Proof of Life after Life: 7 Reasons to Believe There Is an Afterlife by Raymond A Moody is published by Atria Books/Beyond Words Publishing