Twelve-year-old Alex Boesl remained at Children's Hospital of Minneapolis on Thursday afternoon, where he was being treated after inhaling toxic silage gas Saturday morning at his family's farm in Millerville, Minn.

"We have no updates at this point," Amy Revering said by phone Thursday.

Revering has been posting information on a CaringBridge site set up for Alex. On Wednesday, she wrote that the medical staff was "slowly weaning Alex off sedation" and there had been "very few changes in Alex's condition."

Alex's father, Curt Boesl, and his uncle, Steven Boesl, both died of exposure to the gas in Saturday's accident. Steven died after climbing atop the silo trying to save Alex and Curt.

Revering has asked for prayers on Alex's behalf. About 120 people have posted on Alex's CaringBridge site, with thousands more posting on the Facebook page of Alex's mother, Julie Boesl. A GoFundMe page created on Alex's behalf had raised about $40,000 as of late Thursday afternoon.

"I'm asking everyone to please please stop and pray, pray for a Christmas miracle," Julie Boesl wrote on Facebook. "We are completely shattered but we need everyone EVERYWHERE TO pray for my little man."

Silos can fill with carbon dioxide and nitrogen dioxide, gases created by the fermentation of silage, which is fodder for cattle and sheep.