The mother of a three-year-old boy has been charged with the child's murder.
Brendan Owens died at his home on Trinity Terrace in the Tonagh area of Lisburn on July 4.
At the time his death was treated as "sudden and unexplained".
Yesterday a murder investigation was launched and a 27-year-old woman, understood to be the boy's mother Michelle Owens, was arrested.
She will appear at Lisburn Magistrates Court today charged with her son's murder.
A 51-year-old man was also arrested and later released on bail.
It's not clear what new evidence may have prompted police to launch the murder inquiry.
Three houses make up the terrace which has only recently been refurbished.
It is believed that Brendan and his mother had lived there for a couple of months prior to the tragedy.
Many residents were aware of the family and were deeply saddened by the death of the young child, but said they did not see him very often.
It is understood Michelle Owens lived alone and her mother Carol Stephenson, who is understood to be separated from Brendan's grandfather Elton, would often help to look after the child.
Local resident Earl Williamson (56) told the Belfast Telegraph: "I saw him playing in his garden not long before it happened and he was just a healthy wee boy."
A female resident, who did not wish to be named, said the boy's mother had visited her son's grave a few times and was at his funeral.
It is understood that Brendan was due to start school this month at nearby St Aloysius Primary School.
A male resident said that the most important factor is that a child has lost his life and that whatever the conclusion of the police investigation the tragedy remains the same.
It is understood that Brendan attended a mothers and toddlers group run by Barnardos held in a room in St Paul's church hall off the Longstone Road.
The funeral of the three-year-old took place on July 9 in St Patrick's Church in Lisburn.
Lisburn SDLP councillor Patrick Catney said: "It is a real tragedy, terribly sad.
"We need to be very careful as a community how we deal with this and that we help the family as much as possible.
"The community is really devastated."
Brendan Owens died at his home in Lisburn on July 4. The three-year-old had already died when officers were called to the house at around 2.20am. Detectives made door-to-door enquiries to try to establish the circumstances surrounding the boy's death. The post-mortem on his death was inconclusive. Yesterday, a murder investigation was launched.