The baby was taken to a St. Louis hospital for treatment, and he was expected to be released Friday after making a full recovery, ABC News said. Madison County Sheriff John Lakin credited Zobrist with saving the infant's life.
"Fortunately, there is something good that can come of this," Lakin told the Post-Dispatch.
The baby and his six siblings, four boys and two girls ranging in age from 4 to 14, were placed in the care of family members. Community organizations have begun to collect donations of clothing, shoes and toys, as well as monetary donations to help the children replenish what they lost in the fire, the Post-Dispatch reported.
Volunteers are also considering starting a college fund for the children.
The family tragedy began around 5:15 a.m. Thursday when a 911 caller reported a fire at Campbell's home. Though the six older children escaped the flames and ran to a nearby Walmart for help, Justin Campbell's body was found in the house after the fire had been extinguished, the Post-Dispatch reported.
KTVI in St. Louis reported Thursday morning that Cristy Campbell was named a "person of interest" in the fire, and that authorities were searching for her. At the same time, the news station reported the SUV going into the lake just before 6 a.m.
It was initially unclear if the two deadly incidents were related. The connection was confirmed when Campbell's ID was found in the SUV, listing the address of the burned house as her home address, KMOV in St. Louis reported.
A gun was also found in the vehicle, the Post-Dispatch said.
Campbell’s body, which was found about 400 feet from the SUV, was pulled from the lake around 11:15 a.m. Thursday.
The Post-Dispatch reported that security camera footage from a neighbor's home on Dogwood Lane showed an SUV leaving the Campbell home just before 5 a.m. The video, obtained by the newspaper and posted online, showed the headlights coming on around 4:50 a.m. and, after several minutes, the SUV backing out of the driveway.
Some of the children could be seen in the grainy footage, chasing the vehicle as it drove away.
About three minutes later, light from the flames could be seen lighting up the side of a neighboring house. Four of the children, the smallest carrying what looked like a blanket, were seen fleeing past the camera in the direction of Walmart, where they sought help.
Cristy Campbell’s Facebook page is filled with photos of her children and kudos for their accomplishments at school. Her profile photo shows her swimming with a dolphin.
A neighbor, who said she believed that Justin Campbell was living with his ex-wife and children, told the Post-Dispatch that the children were always busy with a variety of activities that earned them awards and trophies that filled their home.
The neighbor, Sherry Ricker, told the newspaper that she saw Cristy Campbell and held her infant son just three days earlier.
“She was happier than I had seen her in a long time,” Ricker said.
Authorities on Friday were still piecing together the timeline of events in the case, but the Post-Dispatch reported that court records show a long history of problems in the Campbells' relationship, including before their 2006 marriage. Justin Campbell was charged with domestic abuse in 2005, when his then-girlfriend was pregnant with the couple's third child.
Cristy Campbell filed for divorce in 2010, but later changed her mind. She filed again in 2012, alleging that her husband was physically abusive. She was granted a protection order against him, but later asked to have it withdrawn.
She was awarded custody of the children when the divorce was finalized later that year, the Post-Dispatch reported. Two years later, she requested that Justin Campbell have supervised visitation after two of the children accused their father of pinching, hitting and choking them.
Cristy Campbell was cited by police three months later for allowing her 5-year-old to leave the house and "wander around the streets of Glen Carbon unattended," the newspaper reported. She was allowed to take parenting classes in exchange for the charges being dropped.