Ryan and Keri Topperwien are making the most of every day with their little boy Chace, after an expensive drug trial they hoped would save his life failed.
The 3-year-old has had a rare and aggressive form of leukaemia since he was 2, and in April began a drug trial at the Royal Marsden Hospital near London.
But when the preschooler's pain increased dramatically after the first of four infusions, the Hamilton family flew home and waited anxiously, praying the drug had worked.
Tests at the Starship hospital last month confirmed the couple's worst fears - the drug was not strong enough to reduce his leukaemic cells.
They had hoped the drug would fight the cancer long enough for Chace to have a second bone marrow transplant, his best chance of survival.
"There is no chance of another transplant," Mrs Topperwien said.
"It would be doomed to failure since he has too much leukaemic cells."
Though there is nothing more medically that can be done for Chace, the couple are using alternative medicines which they say have boosted the youngster's energy.
Mrs Topperwien said the family have researched other drug trials but are realistic about the possibility of success and wary of the side-effects.
And she said that as the strongest chemotherapies, which are effective for many others, didn't work the likelihood of another chemotherapy drug working was slim.
"However there are many other therapies that people have offered and while remaining realistic, we are also open-minded and really appreciate suggestions."
Mr and Mrs Topperwien put their professional lives on hold when Chace was diagnosed, and say they are glad to be spending each day with their boy.
"They [doctors] are unsure about how long he has left so all we can do is make the most of every day.
"Cherish the giggles, smiles and good times, and cuddle, comfort and reassure in the not-so-good times."
The pair have taken Chace home again to Whakatane, where they grew up, and where Chace's grandparents live.
"Whakatane is Chace's turangawaewae. This is where his Ngati Awa and Tuhoe roots are. It's where we feel settled and calm, which is what Chace needs."
Mrs Topperwien said her only child loves being there.
"It has been an amazing transformation to see him perk up and interact with his whanau. He has great memories of fun summers here."
With limited mobility because of lost muscle tone in his legs and increased weight caused by steroids to control pain, Chace knows he is sick.
"There is no doubt that he has some idea," Mrs Topperwien said.
"He is a very clever little boy and people comment on his inquisitiveness and extensive medical vocabulary. But we are always there to reassure him that he is safe."
Chace remains on a long list of medications and needs blood and platelet transfusions every five to six days, but is kept informed by his parents about the treatments he must have.
"He is pretty good at understanding and knows that if we are there, then he will be OK."
The whanau is continuing with a bone marrow drive, which aims to raise public awareness and get more Maori and Pacific Island donors registered.
Fundraising efforts also continue even though the family are no longer appealing for help.
Mrs Topperwien said that without the generosity of the public the family might never have made it to the United Kingdom.
"It is bittersweet. We are glad we tried, despite how scary the whole thing seemed.
"I'm sure one day we will look back on it and be glad we literally travelled to the ends of the earth for Chace.
"It didn't work, but we tried everything and that's all we have the power to do, try."
For more information on bone marrow donation visit bonemarrow.org.nz