The Boston Globe reported authorities said the child, which it identified as Isaih Perez, was discovered uninjured on the streets of Providence, authorities said.
Johnston Deputy Police Chief Daniel Parrillo said Malcolm W. Crowell, 22, was taken into custody at his workplace in Fall River, Mass., during the afternoon and Daniel Rodriguez, 27 or 28, was arrested at a home in Providence.
Police said they expected the two men, whose hometowns were not reported, would be charged in the case by Monday morning, the newspaper said.
The Globe said that while Crowell's name and photo had appeared earlier in the day with a national Amber Alert for the missing child, the alert was updated later to say the suspect was "unknown."
The hunt for the child and the suspects began after police found two bodies on the floor of a home in Johnston about 5:20 a.m. EDT, Parrillo said. Two other older children in the home were not physically harmed and were left behind by the assailants, he said.
The victims had not been identified and he said their relationships to the suspects and the toddler are complicated.
"There's a lot of moving parts when it comes to relationships," Parrillo said. "There are several different families involved, lots of friends and families involved."