While at the hospital he also contracted encephalitis — a brain inflammation.
Jai now lives a life poles apart to most other 2 year olds.
He has a severe brain injury, developmental delays and refractory epilepsy — seizures that are not controlled with seizure medications.
Jai is also non-verbal and can't attend daycare.
For the past year Jaimie and her husband Mike have trialled their son on nine funded anti-epileptic medications.
But none stopped the seizures and some gave terrible side effects.
Jai's only relief is cannabidiol (CBD), an oil-based medicinal cannabis produced by Canadian company Tilray.
It was prescribed by Jai's neurologist at Starship Hospital after the oil was introduced to New Zealand last December.
CBD is found in the seeds, stalk, and flowers of cannabis plants — including hemp and marijuana. It contains no tetrahydrocannabinol — the chemical compound in cannabis responsible for a euphoric high.
Jai is among a small group of New Zealanders, including cancer sufferers and people with chronic pain, now using the oil.
He's riding the wave of change that's hitting New Zealand.
Since last September, doctors could prescribe CBD products without needing approval from the Health Minister.
On January 30 a proposed Government bill allowing cannabis-based medicinal products passed its first reading.
Jaimie is excited about the changes, but says it's about time.
She says her son can't live without CBD, and the four other medications he still takes.
"Before trialling CBD Jai was having up to seven seizures in a 24 hour period."
Now that number has dropped to two or three seizures a day.
He also has some seizure-free days.
"He is now able to concentrate and slow down his movements, resulting in more time to learn and engage with people around him."
Although the oil has been life-changing, it doesn't come cheap, costing the family of five $17,000 a year.
And the price will only soar — as Jai grows his dosage increases.
As Tilray is not a registered medicine, it is ineligible for Pharmac funding.
"Our hope is that one day, CBD might be funded, or at least subsidised," Jaimie says.
But for now, the Bower-Anstis family must pay the full amount.
Jai's illness has taken a big emotional toll on his parents and two older siblings.
The family spends a lot of time away from home in Starship Hospital and Waikato Hospital.
Due to Jai's high needs Jaimie has sold her yoga business to her business partner, and the family is considering selling its home.
But there is a light at the end of the tunnel.
A group of Te Awamutu women have formed a fundraising committee to help raise awareness and funds to contribute to Jai's needs.
They are holding fundraising events, the first this weekend.
• A garage sale and sausage sizzle this Sunday from 8am-1pm at Bowers & Sons, 1852 Alexandra St, Te Awamutu.
• A girls' movie night, screening Finding Your Feet is at Cambridge's Tivoli Cinema on Thursday, April 5 at 7pm. $20 per ticket. Tickets from 0274553878.
• An auction and quiz night fundraiser is on Friday, May 11 at Waipa Workingmen's Club, Te Awamutu, at 7pm. If you would like to donate any items to be auctioned contact Jaimie on 0220417810.
Keep up to date with the family's fundraising on their Facebook and Givealittle pages.