Kat Le Brun's child will be born with an addiction to opioid painkillers after its mother's supply of medicinal cannabis was confiscated by police.
Ms Le Brun was attempting to get off opioids in favour of using medicinal cannabis to manage her chronic pain.
Medical cannabis campaigner Shane Le Brun shared his family's story for the first time at a Parliamentary Select Committee on Monday morning.
He said some years ago he had cannabis seeds arrive in the letterbox - seeds that had a connection to the late Helen Kelly, who campaigned to legalise medicinal cannabis while she dealt with terminal lung cancer.
"A couple of weeks [after the seeds arrived] I got a phone call from Helen Kelly, and she joked, 'Did you get any nice surprises in the mail lately?' I'm not saying it was her directly, but perhaps one of the green fairies that she had contact with had arranged it."
Mr Le Brun said he then took it upon himself to cultivate the seeds for his wife, but they were taken by police a month from harvest.
"The police counted 20 plants. They came when we were not home," he said.
"They took it all, and the end result of that [is] Kat's 14 weeks pregnant, and our next child's going to have to go through opioid withdrawals, and we've already had to go through that with the first."
The pair were jointly charged for growing the plants.
Ms Le Brun said she had to watch her first son go through withdrawals from methadone - the opioid pain killer she was on for long-term pain management.
"I blame myself because I couldn't get off the pain killers," she said.
The topic of the submissions means many are sharing emotional stories. They are stories of dealing with chronic pain and caring for people with terminal illness.
One submitter spoke of a close relative he identified only as Jane, who has been told she has 18 months to live.
The submitter told politicians at the Select Committee the Bill's legal defence which will allow people with one year to live to use cannabis without prosecution is a cruelty.
"It is going to demand she convince people she has less than a year to live when she is trying to live as long as she can," he said.
"Having a time limit on those condemned to die... Those people need every help to maximise what they have left."
The Government's Bill will allow medicinal cannabis producers to set up in New Zealand. That could take a couple of years to develop, so the Government has written a temporary legal defence for the terminally ill who have one year to live.
The legal defence has come under much criticism during the Select Committee process.
The most common criticism is that the defence should be widened to include people with chronic pain. There is also criticism around who could still be prosecuted for helping out the terminally ill.
The terminally ill will be able to use cannabis but not grow it, the implication being they will need to buy it off the black market. But anyone who supplies cannabis to the terminally ill will not be exempt from the law, and carers will not be entitled to the legal defence if they were to procure on the terminally ill's behalf.
The Bill passed its first reading with support from every MP in Parliament. It is likely to pass into law, but questions remain over how much the Bill could be modified during the Select Committee process, and whether the legal defence could be widened.