A TOOWOOMBA family is living with the heartache of an illness that could kill their child any moment - and they still don't know why.
In July 2011 Lachlan Miles was kept home from school because he was unwell.
Lachlan's father Greg walked into the living room and found him in a massive seizure.
His mother had just taken her own mother to hospital and returned home to find another ambulance in the driveway.
When they got to hospital they found out it was a serious seizure.
At first the family thought it was a one off seizure.
But days later he had another seizure.
In the last 4 ½ years he's been to 11 hospitals and hospitalised 117 times.
The Toowoomba boy is only hospitalised for major seizures.
He generally has about five seizures a day.
Ms Miles said 2012 was a particularly bad year, with Lachlan spending eight months in hospital.
From the outset doctors didn't know why he had seizures.
One theory was a virus had attacked his brain, another that he had an autoimmune disease.
In 2013 the family became aware he had a pituitary cyst that was growing in his brain.
He had brain surgery on that in 2014.
It's unclear whether the cyst is the cause of the seizures.
He is one of the few patients in Queensland with a vagal nerve stimulator, which is supposed to help reduce the frequency of seizures.
The surgery did help reduce the severity of the seizures.
Rather than needing a whole range of drugs, at times he can be withdrawn with the common epilepsy drug midazolam.
The family carries other more powerful drugs, but they can only be administered in an emergency department.
Lachlan's mother Rhonda has been a long-term advocate for medical cannabis to be introduced in Australia.
A medical cannabis trial will start next year at the Lady Cilento Children's Hospital, with the $3 million program to give children with severe epilepsy access to treatment.
The family receives support from Disability Services Queensland and Queensland Health.
Carers watch Lachlan from 10.30pm until 7am, allowing the family to sleep.
That care allows the family to keep him at home.
The medications he takes, which include substances like phenobarbital, have severe mental side-affects including psychosis.
The legal drugs which are required to help him have left him with severe mental health problems.
He doesn't go to school because he's battling a mental-health as well as a physical battle.
Ms Miles said the family had been overwhelmed by the support from the Toowoomba community, ambulance service, Toowoomba Hospital - one of the ED nurses baked a cake for his birthday - and support from school communities.
The family knows the ambulance service so well they can tell when paramedics have had a hair cut.
But Ms Miles said their life wasn't all doom and gloom.
"Yes the seizures are life threatening and we don't know how long we're going to have Lachlan.
"But we try to live every day and enjoy it.
"We even let him tube behind a speed boat if he's feeling okay.
"We don't just want our memories to be of hospitals, we want the good bits too."
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