The teenage son of former All Black star Corey Jane constantly asks his parents: "Why does it have to be me that has seizures? Why can't I be normal?".
Cassius Jane has recently undergone EEG (Electroencephalograms) tests at Auckland's Starship Children's Hospital to determine if he will need surgery to curb his epileptic seizures.
His mother, Amie Jane, told the Herald on Sunday Cassius has "abnormal growth" in his brain. She doesn't want to dwell on the possibility her son might need brain surgery.
"Hopefully the tests will locate where the seizures are happening and if the tumours can be removed. He might need an operation but it depends where the activity is.
"There are parts of the brain which aren't safe or they can't get to. I don't want to think about it too much otherwise I'll be a wreck."
Cassius has previously been diagnosed with tuberous sclerosis, a rare genetic disorder which can cause epilepsy, autism and ADHD.
"He was the first in our family to have this mutant gene. Cory and I were tested, we don't have it, neither do our other kids."
Cassius, who turned 13 last month, towers over his siblings Tennyson, 9, Prisseis, 8, and Iradessa, 6.
Amie said in many ways Cassius was like his rugby star dad, "funny and cheeky".
But she added: "He can fool people and comes across as normal. But his intellectual level is that of his [6-year-old] sister. He loves super heroes like Batman and Spiderman and his recollection of songs is extraordinary - he raps to Eminem songs no problem."
Cassius's seizures are regular, unpredictable and at times violent. At a family holiday last Christmas he had them every second day. The teenager is "passionate" about the sea but while he was under water looking for fish he had a "massive" seizure.
"A wave bowled him over and when he didn't surface Cory pulled him out and lifted him on to his shoulder."
The seizures were random and the family have learnt to recognise the warning signs.
"He might turn his head, he gets a blank gaze on his face, braces himself and tries to hold on to something. He's had some pretty big scares and near misses."
Cassius relies on high dosages of medication three times a day.
His parents are extremely grateful to the doctors and specialists at Starship and are open to the idea of trying medicinal cannabis; epilepsy is one ailment which has seen cannabidiol prescribed to sufferers.
But treatment can cost up to $2500 a month and Amie said they didn't want Cassius to be treated like a "guinea pig".
Cassius attends Intermediate school in Upper Hutt and enjoys woodwork, swimming and basketball. School provides routine and socialisation for him but he can't play team sports, his mum said.
She said while she can get frustrated, her husband is more relaxed.
"Cory is more chilled and laughs it off but for me it's an on-going battle. It's tiring and can be frustrating."
Like any mother, Amie worries about her eldest son's future.
"I have to hold back the tears because I wonder, 'Is it likely he will find a little girlfriend and marry? Will there be medical advancement so he can have his own children and not run the risk of passing on his condition?'."