The toddler was thought to have fallen from a window at the property in Plymouth.
She was in the hospital with internal injuries and doctors said that she was in a "stable condition," the 'Mirror' reported.
The tot was taken to the city's Derriford Hospital where she is being treated.
Police is not treating the incident as suspicious and no one has been arrested, the report said.
"There have been no arrests and we are not treating the incident as suspicious," a police spokesman said.