Mikah Arvidson had been excited all month to go trick-or-treating dressed up as Master Chief from his favorite video game Halo.
But, on Halloween night, the six-year-old was complaining that he wasn't feeling well and didn't want to go anymore.
His parents, Blake and Aubrey, assumed their youngest son had caught a 24-hour stomach bug but, after three days of constant vomiting and Mikah complaining of abdominal pain, they rushed him to the emergency room.
Doctors discovered 14 tiny magnets were inside his small intestines had perforated the lining and were leaking bile into his stomach.
That's when the first-grader, from Sandy, Utah, told his parents he had been secretly playing with his brother's fidget toy - but when his brother walked in on him, he rushed to hide them in his mouth, inadvertently swallowing them.
Two weeks on, Mikah remains hospitalized, unable to eat or drink anything and having undergone three surgeries as doctors work to repair the damage.
Aubrey told DailyMail.com that it was around 8pm on Halloween that Mikah vomited him for the first time.
'He kept saying: "I don't feel good, I don't feel good, my stomach hurts", ' she said. 'He kept vomiting every 30 minutes and then kept throwing up about once an hour through the next day.'
Over the next three days, Mikah was complaining of pain his abdomen, unable to keep food or water down, and was too weak to walk.
On November 3, realizing that he was dehydrated, his parents rushed him to the emergency room of Primary Children's Hospital in Salt Lake City.
Doctors gave Mikah pain medication and started an IV, drew his blood and performed an X-ray.
'When they did the first X-ray, they were like: "Does he have a zipper on his pants because something is showing up on the screen?"' Aubrey said.
'So they redid the X-ray and it was still there, and the whole feeling in the room was of panic.'
Doctors rushed Mikah into emergency surgery, where they discovered the 'zipper' was actually 14 magnets, each no bigger than the size of a pinhead.
The magnets had clumped together in his small intestine and perforated it, leaking bile into his abdomen.
It turned out the magnets were Zen Magnets, also known as neodymium magnets, which are small spheres that have been marketed as educational toys.
Aubrey and Blake had bought them as a fidget toy for their oldest son Kurtis, 11, who has ADHD.
Mikah later told his parents that he had gone into his brother's room and was playing with the Zen Magnets. He had hid them in his mouth when his brother walked in.
'He told us he swallowed them but thought it was only or two and didn't think anything of it, so he just forgot,' Aubrey said.
'I was in disbelief that my six-year-old would swallow something and not tell me. We were in complete horror that they were sitting inside of him for three days.'
Mikah has undergone three surgeries so far to repair the damage done to his intestines, hasn't eaten or drank anything since Halloween, and has had high fevers every single day.
He also told his mother that he wanted to warn other children about his experience.
'He's told me: "Mommy I wish I could go back in time and ask my brother if I could play with his toys and I hope I can tell all the kids in the city not to do this",' Aubrey said.
Aubrey recorded three messages from Mikah on her phone and posted them online.
An investigation from the US Consumer Product Safety Commission (CPSC) in 2012 found an increase in young children and teens ingesting the magnets since 2009.
A lawsuit filed by the CPSC in 2014 resulted in the ban of Zen Magnets and a similar product, Buckyballs
In November 2016, however, the US Court of Appeals for the Tenth Circuit reversed the ruling in favor of Zen Magnets because only Buckyballs had ever issued a recall of their products.
'These magnets are dangerous and, with Christmas coming, we don't want these to become a stocking stuffer,' Aubrey said.
Family friends have set up a GoFundMe page to help the family cover Mikah's medical bills.
So far, more than $1,600 has been raised out of a $10,000 goal.