Police say the assault was reported last month after the boy told his parents of the alleged assault at a home in the city's northwest in December.
The suspect is not a childcare worker, but lives in the residence and is known to the dayhome operator.
He is alleged to have assaulted the child when the two were alone.
Miles Jarvis Clark, who is 51, was arrested last Thursday on a charge of sexual interference with a child under the age of 16.
Police say they're attempting to contact parents who may have had children attending the dayhome.