A manager at the Walmart, located at 4501 Rosewood Drive, had stepped outside to take a break at about 3 a.m. and found the boy in the parking lot, barefoot and wearing only a white T-shirt and a diaper, police Sgt. Maria Munayer said.
The manager called police, who searched the area but were unable to find the boy's parents, and officers brought the boy to the Child Protective Services intake center, Munayer said.
At about 6 a.m., police received a frantic 911 call from a woman who said her young son was missing from her home at the Archstone Hacienda apartments, across Owens Drive from the Walmart.
It appears the boy let himself out through the front door, which was built to Americans with Disabilities Act standards to accommodate people in a wheelchair, Munayer said.
"It would have been pretty easy for the child to have gone out the front door because the apartment is ADA compliant, meaning that the door handle is positioned very low on the door," she said.
The child was uninjured and is in "very good spirits," Munayer said. He has been reunited with his mother.