"It has turned our whole family's life upside down ... it is so very hard to accept this has happened to both my babies. Having two babies with cancer is a mum's worst nightmare."
The twins need bone marrow transplants and the family faces an agonising wait over Christmas to find out if either parent or two-year-old daughter Oaklee will prove a match.
"My two older kids have a different dad, so the best chance for the babies to get a match comes from me, Vaughn or Oaklee. If there is no match, then we will have to go on a worldwide waiting list for a suitable universal donor."
The family is determined to have a normal Christmas at home in Rotorua.
Archer expects to stay with the twins at Starship from January while the boys get treatment expected to last between two and five months.
"Our other kids know their wee brothers aren't well but they have no idea how serious it is," she said.
The family has set up a fundraising page on the Givealittle website and has launched a Facebook page to follow the twins' progress.
"Vaughn is going to have to keep working to pay the bills as well as look after our other three children while I am at Starship with the twins," Archer said.
"We are hoping to raise about $5000 to allow Vaughn to take some time off and live at Ronald McDonald House with the kids.
"It is not so much the money we are bothered about, we just want as many people as possible to think good thoughts for the babies. We appreciate all the good wishes and messages of support we've been receiving for our little fighters to help us through this nightmare."
Juvenile Myelomonocytic Leukaemia accounts for about 1 per cent of all childhood cancers.
Professor Bruce Baguely, co-director of the Auckland Cancer Society Research Centre, said it was very uncommon for children to get the disease in New Zealand.
"It is a rare occurrence for one person to get this," he said. "I have never heard of twins getting it before."
To donate to the family's cause, visit: givealittle.co.nz/cause/theoandlaken