In the front room of their home on the Kent coast, Jo and jason crews are looking at a stream of Facebook comments. On the eve of our meeting, they shared a post on a private Facebook page with the latest news of their grieving family and friends. Jo was overwhelmed with emotion and read out a few of the responses. One person says that she is very giving until the end. From the start, we are all firmly in the thick of things.

She died from a rare form of cancer at the age of 30. She was raised in the same house as us. During her last few months, it was here that she came back to. The love they feel for their daughter is clear in every word they say. They have made every effort to see through their daughter's last wishes, even though it was hard at times.

Next month, a new documentary will be aired. Her story will be shared with the nation. There are interviews with loved ones, as well as her diagnosis, in it. She will be filmed under strict medical supervision and viewers will see her body being sliced open.

It is meant to educate viewers on the science of cancer and its journey through the human body. In order to support decades of research and improve the lives of countless people, her parents wrote that they wanted to understand what caused her symptoms. It's understandable why Jo and Jason wanted to give those who knew about her a heads-up.

Full of life: an early picture of Toni.

Full of life: an early picture of Toni.

They thought this was an extension. It was easy to observe. I distanced myself from it because it didn't look like me.

Jo smiles and says they always watched CSI. One of the medical team cries her eyes out during the minute's silence, which is the more personal side of it. This journey was touched by so many people, even though it was made by someone else. She wanted to be a force. She will do that for millions of other people.

extracts of diary entries, messages and social media posts are included in the narration of the documentary. Filmmakers used artificial intelligence to duplicate her voice in archive recordings. It seems like she is with you as the story progresses.

Both of her parents say that her caring nature was obvious from her earliest years. She dropped out of an occupational therapy course after taking it. She started her own family after finding a job in a care home. At the end of 2016 she began to experience headaches. She told her parents that it was a rare cancer.

Pictured: Professor Claire Smith Deputy Pro Vice Chancellor Education and Innovation. Head of Anatomy Brighton and Sussex Medical School

‘We needed to know how her family felt before making the film’: head of anatomy Professor Claire Smith. Photograph: Richard Ansett/Channel 4

She told us it was nothing to be concerned about. That won't prevent a mother from being a mother. By all accounts, there was a good chance that Toni would live. She had a major operation the next month. The best chance of survival was the removal of her eye. Jo needs to take a break.

The surgeons were confident that they had removed all of the tumours. We weren't too worried with the positive attitude of her doctors. A single mother of two young children, she had little to worry about. It took a while for life to return to normal. The headaches began to come back sometime in the middle of the year.

After her surgery, the medics thought it was the nerves that were the problem, but a Scan showed there was more than one small Tumour. After a few months, she underwent her second surgery. He says that she was taken to Charing Cross Hospital to have her soft tissue and bone sockets shaved. I walked up and down the river for five hours. All signs were good after the procedure.

January 2020 saw a turn in Toni's health. There was a small mark on her back after she coughed. Doctors delivered their diagnosis by the end of the month.

The cancer had spread to other parts of the body, but it was still back. She began treatment within a month. Her health deteriorated as a result of that time. Both parents are devastated by this time. They both made it clear that is what she wanted. She was taken to the oncologist on July 23rd. He said it was moving too fast. He didn't know how long she had, but said that we shouldn't waste our time in the hospital. She died at home.

Making the best of things: Toni models a brightly coloured eye patch.

Making the best of things: Toni models a brightly coloured eye patch

In the last weeks of her life, she put others first. She taught her children about grief. A family trip to Legoland was organised by her. Practical discussions were also going to be had. It was a given that we would take the children. The most heartbreaking of parent-child conversations was about what to do to her body.

In the past, Toni had told her parents about her desires. Through the years that she had been fighting cancer, she had run online pages educating people about the illness. She would post about what to look for. She wanted other people to be aware of their surroundings and to take precautions.

When she mentioned that she wanted to donate her body to science, it came as no surprise to the two. She came out of the kitchen with a bunch of forms. She asked us to be her witnesses after printing them all out. It was easy for her to understand.

It was a typical thing to do, according to the man. Do anything she can to say yes to everything. We talked about how they could keep her body for a while and how they could take pictures. We didn't know how revolutionary she wanted it to be. I don't know if she did as well.

Jo and Jason: ‘Toni used to post about symptoms, what to look for, what you can do.’

Jo and Jason: ‘Toni used to post about symptoms, what to look for, what you can do.’ Photograph: Roo Lewis/The Observer

Things were put in place in the days leading up to her death. An expert team was called into action after she passed away.

The service of donating bodies to medicine in death at medical schools in the UK is very important. They are often referred to as the institution's "silent teachers".

Smith sat across from me at the kitchen table while the couple had their picture taken next door. There is a growing need for donors in the UK. You want to know that the healthcare practitioners are confident in the structure of the human body and how to engage with it. Students receive hands-on practice from donors. Their value is extended to professionals in planning and developing new surgery techniques.

Smith says that consent happens in life. Some join on their 18th birthday, others only join after being diagnosed with a serious disease. If you can be photographed or made anonymous, you can specify the limits of what you agree to on the forms. All medical schools have to follow strict regulations when using donors.

Smith says that medical schools can only use the donors to train healthcare professionals. Behind closed doors, anatomical teaching is still being done. The first medical school to have permission to display body parts is BSMS.

She says that it gives them permission to use a donor's body to educate others. Personal trainers and yoga teachers are also included. There can be real medical problems if these professionals don't know what they're talking about. Both in causing harm and not knowing what to do. This licence also applies to public education.

A medical school is notified when a donor dies. The paperwork was picked up by Smith. She was the first donor to do so with the school's new licence. The possibilities seemed endless. She says that it was a rare cancer. It's one in a million. There was a lot of learning to do from it for our students. The crews family was contacted by her.

She says that they needed to know how her family felt. The idea of a documentary came about as conversations grew. It was the sort of thing Toni would have liked. The value of a film was obvious to Smith. She says that one in two people will be diagnosed with cancer. I've had it. This was a chance for people to understand what cancer is and how it can be treated.

Smith's team worked closely with the family to come up with a plan. She says that they invited students from across the universities. There was a lot of research done. Various scans were arranged and the team talked to the doctors who treated her. Smith said that they talked to the family about how her illness had developed and how she had experienced it. Medics rarely get access to this type of knowledge. To help trace the journey of cancer through her body, she says, we pieced together the fullest picture possible.

More than one thousand students sat through sessions in the school's clinical dissection room. Smith and her colleagues traced the progression of her cancer from the eye to her neck. The result is not for the faint-hearted. It is the first time a dissection of a named donor has been done in front of a public.

Smith thinks that this format is a huge undertaking. She says that it helps develop people's knowledge of the human body for those who attend in person and watch it on tv. It is possible for viewers to know what is happening inside their own bodies. If it makes other people think about their health, a career in healthcare or body donation is a possibility. All the best. Smith said that it was clear to her that she wanted to make sure no one else went through what she did. This is a step in the right direction.

The kids are living with their grandparents now. The family has considered how the film will be handled. Jo says that it will be online for a while. They shouldn't be stumbling on it. They can make an informed decision when they are older. They know there is a film about their mother and she is teaching doctors. Should they ever want to read her file, it will be kept at the medical school.

There wasn't a funeral when she died. Her body was handed over to her coworkers. After the medical work was done, she was returned to her family in July. The grieving was paused while the research took place. It was as if she was still with us when we talked about her. The family held a cremation service. Next week will be the end of this chapter.

She will continue to educate because the medics have kept parts of her for many years. Hundreds of medical students have learned a lot from the teacher. One person watching a film and getting a lump checked saves a life. We couldn't be more proud of our daughter.

The show is on Channel 4 on December 5.