A mother and her boyfriend were charged yesterday in connection with the death of a 4-year-old Bronx boy, Quachaun Brown.

The boyfriend, Jose Calderon, 18, was charged with second-degree murder for allegedly beating the boy to death because of an overturned television. Quachaun’s mother, Alicia Smith, 26, was charged with second-degree manslaughter for allegedly failing to rescue her son. Both defendants awaited arraignment last night, according to the Bronx district attorney’s office. If convicted, Mr. Calderon could face up to life in prison; Ms. Smith could serve a maximum of 15 years.

Quachaun died after the city’s Administration for Children’s Services – which has come under increasing scrutiny after the deaths of several children in its system – had already conducted eight investigations into allegations of abuse or neglect in the child’s home.

The commissioner of children’s services, John Mattingly, said, “After reviewing the history in this case, the obvious evidence of chronic neglect should have prompted a stronger response rather than addressing and resolving each incident separately. However, nothing in the record suggests ACS failed to act in a way that might have prevented this fatality.”

As people tried to make sense of the latest child fatality, new details in the case emerged.

On Friday after 3 p.m., a television fell to the floor of the Kossuth Avenue apartment where Ms. Smith resided with Mr. Calderon and five of her six children. One child reportedly lives with a grandmother in Brooklyn. The cause of the crash was unclear, but police officials said Mr. Calderon held Quachaun responsible and beat him. This was not the first time Mr. Calderon had inflicted violence on Quachaun, officials said, or on the other children.

Investigators said they believe Friday’s beating continued into the following day, when Quachaun became sick, throwing up blood. Ms. Smith apparently awoke during the night to find Mr. Calderon attempting to resuscitate Quachaun. She dialed 911, and Quachaun was taken to North Central Bronx Hospital, where he was pronounced dead.

Hospital officials reported that Quachaun suffered a fractured skull, the authorities said. Law enforcement officials said Quachaun’s injuries were consistent with those of someone who had been punched and slammed against a wall. The medical examiner’s office had not yet ruled on the cause of death as of yesterday.

Mr. Calderon – who was previously arrested on charges of grand larceny, criminal possession of stolen property, and unauthorized use of a vehicle – moved into Ms. Brown’s first-floor apartment in August. The same month Quachaun’s father, Mandinga Brown, 24, left the apartment because he was arrested on charges of robbery and held on $40,000 bail at Riker’s Island, where he remains, officials said. Brown has a criminal history with arrests dating back to 1999, and five convictions for robbery, trespassing, and disorderly conduct, authorities said.

Administration for Children’s Services has had a 10-year history with the Brown family, agency officials said. The agency has conducted eight investigations into allegations of corporal punishment by belt of one of Quachaun’s siblings, failure to supervise children properly, poor housekeeping, insufficient food for the children, and excessive absence, agency officials said. One investigation allegedly deemed a burn Quachaun suffered accidental.

On November 15, the most recent incident, the agency received a call from the school attended by the three oldest children, which did not include Quachaun. The school said they were frequently absent, were sent to school hungry and without adequate clothing, and were not well supervised, agency officials said.

The five children – girls ranging in ages from 9 months to 9 years old – are now in the custody of children’s services.