The older brother of the two children hospitalized said they should be discharged from the hospital Wednesday night.
Josh Vue was also treated for carbon monoxide poisoning, but said it didn't affect him as much as his siblings because of his age.
"I felt a little bit of pressure filling in my head," he said. "I felt like my hearing was a little bit off, I felt like I was in space for a little bit."
Vue said his parents planned to buy new carbon monoxide detectors after the one in their home did not work and alert the family of the problem in their home. The Green Bay Metro Fire Department says the detector didn't work because it was old and needed to be replaced.
The GBMFD is reminding people to check their carbon monoxide detectors monthly and replace them when needed.