They were born 60 seconds apart, but 3-year-old Finn Dale towers over his twin brother Toby. Despite being identical twins, the boys couldn't be more different physically with Finn weighing 6kg more and wearing clothes four times larger.
Toby has a rare growth disorder called Russell-Silver Syndrome which affected how fast he grew in the womb and his growth afterwards. He has never been able to catch up to Finn, who is above average for his age in weight and height.
The twins' mother, Jacquie Dale, says having identical twins highlighted how behind Toby was developmentally.
"It's been harder, but now for me it's clearer too because they are identical twins so the gap is getting bigger and bigger."
The boys, who live in Hamilton, were born 11 weeks premature - Toby weighed a tiny 480g and Finn 1.35kg. Both were in Starship hospital's Newborn Intensive Care Unit (NICU) but while Finn went home on his due date, Toby stayed another six months until he could eventually be taken home, with oxygen and feeding tubes attached.
Mrs Dale and her husband Tim call Toby their little miracle because he spent his first year fighting for survival and was in hospital more than 250 days for the first three years of his life.
Premature babies normally catch up by the age of 2 in growth and development, but Toby never did.
His failure to gain enough weight, poor appetite, bad reflux and triangular face are all characteristics of Russell-Silver Syndrome, which he was diagnosed with a year ago.
The biggest challenge for Mrs Dale, a trained nutritionist, is getting enough nutrients into him as Toby cannot keep food down and has to be fed high-calorie formula through a port in his stomach overnight and three times a day for an hour. He carries a hospital pump around in a backpack and the feed is slowly taken in while he's playing.
Mrs Dale has struggled to find out information about Russell-Silver Syndrome and wants to take Toby to a conference in Chicago in July, run by the Magic (Major Aspects of Growth In Children) Foundation. They have an appointment with two world experts in the field and want to find out more about growth hormone drugs commonly used for children with growth disorders in the US and whether Toby would benefit from them. The drugs are not subsidised for New Zealand children with Russell-Silver Syndrome and would cost tens of thousands of dollars a year. Toby would need to start taking them before he turned 4.
"It's been really limiting here," Mrs Dale said. "Because most of the other babies that are tube fed here are tube fed for different reasons in New Zealand. They might have cerebral palsy and they might have specific reasons they can't eat, they still grow and get enough calories. With Toby it's a battle getting him to grow."
The Dales are raising money through Givealittle.co.nz to attend the Magic conference.
*Genetic condition characterised by severe intrauterine and post-natal growth restriction.
*The rare syndrome was first described in 1953.
*Ranges from 1 in 75,000 births to 1 in 100,000.