A woman and a child were hospitalized for smoke inhalation after a two-alarm fire broke out in a Roxbury apartment building Sunday evening, fire officials said. Both victims left the building on their own volition and are expected to be OK, a Fire Department spokesman said. The fire in the four-story, 14-unit brick building at 55 Brookledge St. caused an estimated $250,000 worth of damage, the Fire Department said. Firefighters responded to the scene shortly before 7 p.m., and found the fire burning on the second floor, the department said. It later spread to the third story as well. The fire was declared extinguished after about 45 minutes, officials said. Investigators were trying to determine the cause of the fire Sunday night.