CHESTERFIELD COUNTY, Va. -- Eight-year-old Macy Roberts said she has special permission to sit here at a desk in a room that is not her own.
"I know Carter is around me," Macy said.
On the desk, a little chest filled with memories of the boy who used to live there.
"Whenever I'm in here, and I start feeling sad or down about him, I can get a slip of paper back here, and I can write stuff about him," Macy said.
Three-year-old Carter Nolan Roberts unexpectedly got sick back in July 2016 at his Chesterfield home.
"We had pizza that night, and he got sick to his stomach shortly before the meal was over," Carter's mom Robin Roberts said.
Not even 48 hours later, the boy couldn't hold up his head or use his right arm.
"He was on the floor in a ball saying 'mommy, mommy help me. Help me,'" Roberts recalled.
Roberts took her son to the emergency room, but still, she got few answers as to what was wrong.
"The first doctor we saw there in the ER looked at me and said, you know mom, when kids get sick, they can get really tired," Roberts remembered.
By the next morning, Carter could not breathe on his own.
"He would never come off that breathing tube again... at all," Roberts said.
Carter was eventually intubated and then came a diagnosis.
"It took just shy of two weeks for them to tell us, definitely, to tell us he had acute flaccid myelitis AFM," Roberts said.
AFM is a rare polio-like illness that impacts the nervous system.
It's not new, but the numbers are rising.
"There are outbreaks every year in late summer and early fall," Roberts said.
There is no cure and no definitive cause.
And, over 90 percent of those impacted are children.
"That's the question. Why do some kids get this and others not?" Roberts asked.
Since 2014, the CDC has confirmed 430 cases of AFM throughout the U.S. with an additional 167 cases under investigation this year.
"Carter has not been counted in the numbers," Roberts said.
Despite being diagnosed with AFM at three different hospitals, Roberts said Carter's case remains under investigation.
"I find it hard to believe that a two-and-a-half-year lag is responsible for his case not being counted," Roberts said.
Not every case ends in death, but Carter's did on September 22 of this year.
"As his numbers went down, I screamed for his sister to come in and hold his hand, and within a couple of minutes the last thing he said to me was ‘mommy I am fine’ and he closed his eyes," Roberts said.
Now, Carter hangs out in the family room.
"I usually kiss my hand and kiss the urn," Roberts said.
Macy even talks to him.
"Whenever I come in here to work, I feel like he's right next to me and he's telling me what to make," Macy said.
She finds comfort in the narrative she's writing inside her tiny memory box of her brother's short story.
Roberts said she met with the CDC last week with several other families impacted by AFM.
She said the CDC is now forming a task force to investigate the condition further.
The Virginia Department of Health sent a letter to clinicians earlier this month urging them to be on the lookout for AFM and report any suspected cases to their local health department.
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