They are the tender and heart-warming words of people who owe their lives to the generosity of those surrounded by tragedy.
The moving letters written by transplant patients and their families have been turned into a book to encourage more people to sign the organ donor register.
Thank You For Life has been compiled by Professor Andrew Burroughs. He is responsible for passing on letters from transplant patients to the family of their donor. With the consent of everyone involved, he decided to bring some of the moving messages together in the book.
Professor Burroughs, consultant physician and hepatologist at Royal Free Hampstead NHS Trust, said: "My colleague Linda Selves, a transplant co-ordinator, and I have been thinking about this for four years.
"We see the results of transplantation but realised there wasn't enough thanks going to our donors. We believe they should be recognised and celebrated.
"The book is a first step in that process and illustrates transplants are about people and not organs.
"At the launch, I suggested we start a campaign to use the fourth plinth in Trafalgar Square for a monument to donors. The square is dedicated to unknown heroes and the donors are certainly that.
"Almost all families are pleased to receive these letters because it is confirmation some good has come from their loved one's death.
"Even though it reminds them of the sadness, I do think it helps with the grieving process.
"Of course, we hope the book encourages more people to sign the organ register."
Here, we take a look at a few of the letters in this touching collection, published by the Royal College of Physicians for NHS Blood Transplant.
Helen Eccles was given a life-saving liver transplant two days after her daughter's birth in 1996. In her letter to the donor's family, she wrote: "Without the transplant, I would certainly have died, leaving my husband to look after our new-born baby on his own.
"Like most transplant patients, the gift of life has been amazing and words can never express just how grateful we really are. I enclose a picture of Ella, our baby."
Helen wrote again to the family recently. She said: "It's a relief to be writing again ... to reiterate my deepest heartfelt thanks to you all for the amazing gift of life that your grandmother and mother gave me, my friends and my family, by donating her liver to save my life.
"I have so much to be grateful for and to celebrate that is marvellous and I am pleased to say that one of the legacies of being a transplant patient is that I really appreciate the small things in life.
"Being able to spend time with family and friends is so important to me, as is doing the most ordinary things with them.
"My daughter Ella is now a beautiful teenager and every year on her birthday I am reminded how blessed we are because that is the time of my transplant."
Joan's letter was in many ways the inspiration for the book.
It was read out at her memorial service by her grandchildren, almost 20 years after her liver transplant. She said: "When I had my transplant, there was a very strong feeling of what I can only describe as love among us all. I felt proud and humbled to be part of the team. Transplantation is much more than a physical miracle.
"It is a bonding of humanity, and it has altered and enhanced my life in so many ways. I cannot adequately express my gratitude."
Simon had his first transplant in 1994 for liver failure. Two months later, he had to be listed for a second, and for a third eight years later.
Following his final transplant, Simon married fiancee Tansy and nine years on he enjoys good health.
His mum, Maureen, has routinely written to Cathy, the mum of Simon's donor, Emma.
In one letter, she said: "Thank you for Emma's photograph. She was beautiful. I have not shown it to Simon. I do not think he could bear to see it. He is so conscious she has enabled him to live.
"When Simon was in ITU after his transplant, Tansy used to talk to Emma's liver. She welcomed it, said it was now safe after its trauma and told it about Simon. That he was gentle and would look after it."
Deborah had her transplant 12 years ago and remains well and grateful for this amazing gift. In her letter to her donor's mum, she wrote: "It feels good to be able to thank you from the bottom of my heart for the gift of life your daughter has given me and for the kindness and compassion you have shown.
"My name is Deborah and I am 39. I am engaged to Mark and we are planning to get married in May this year.
"I want to say to you it was a wonderful thing you did as a mother that in your deep sadness showed a caring and giving heart.
"I have a much better quality of life now since coming off dialysis five years ago. My father died of kidney failure when I was three.
"I often think about your daughter, who she was and what she was like. Despite not knowing her, I think about her with affection and much respect."
Susan Lee-Clark had chronic liver disease since she was 11. Five years ago, she was so ill she didn't leave her room for 18 months.
In her letter, she said: "I watched a year in my son's life tick past.
"Family life was not good, my husband's work suffered and he became extremely tired and desperate as he took on more and more responsibilities in the home.
"To give you a small example of just how much your gift has meant to us, please imagine this.
"My son Harry and I were at our local play area last week and I was able to help him ride his bike without stabilisers. We had smiles and tears of joy and the glow of confidence beaming from Harry.
"I can honestly say the memory of the three of us just "being", smiling, holding each other and crying will live with me forever."
Dad-of-four Steve, 37, was diagnosed with liver disease about five years ago. In his letter, he says: "I would love the donor family to know their brave decision not only saved my life, but it transformed all our lives. We've been able to move on from illness and benefits."
John was 14 when he had his kidney transplant. That was eight years ago and he is still fit and well.
His younger sister Sarah wrote to the donor family, saying: "Thank you for making my brother's life better.
"We're all happy he has had his transplant.
"He is happy as well."
NOTE FROM MERV
Also please read the heartwarming exchange of letters between a lung transplant recipient and her donor family that was posted here in September.
“You Have the Power to Save Lives – Register to be an organ and tissue donor & Tell Your Loved Ones of Your Decision”
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Your generosity can save or enhance the lives of up to fifty people with heart, kidneys, liver, lungs, pancreas and small intestine transplants (see allotransplantation). One tissue donor can help by donating skin, corneas, bone, tendon, ligaments and heart valves
Has your life been saved by an organ transplant? "Pay it forward" and help spread the word about the need for organ donation - In the U.S. another person is added to the national transplant waiting list every 11 minutes and 18 people die each day waiting for an organ or tissue transplant. Organs can save lives, corneas renew vision, and tissue may help to restore someone's ability to walk, run or move freely without pain. Life Begins with You