Detectives investigating the death of six-year-old Matthew Healy in Waterford are hoping to receive medical clearance to question a woman later today.
The child was found unresponsive in a car near Rathmoylan Cove outside Dunmore East shortly after midnight last Friday.
A 38-year-old woman was arrested at the scene and is being held at a Garda station in Waterford.
A vigil was held for Matthew yesterday as the people of Waterford expressed their "deep" shock at his death.
Irish Times Security and Crime Editor Conor Lally told The Pat Kenny Show the woman has been undergoing medical checks over the weekend.
"The woman who was detained in the early hours of last Friday morning has been undergoing checks and treatment since then," he said.
"She hasn't been interviewed by the Gardaí.
"We know that she raised the alarm at the scene at Rathmoylan Cove near Dunmore East.
"It appears the woman raised the alarm by calling to houses nearby.
"One of the people that she called to became quite concerned, they rang the Gardaí and then Gardaí and paramedics arrived on the scene."
Mr Lally said the young boy was found unresponsive in the backseat of a car and was declared dead at the scene.
"The woman who had called to the houses about half an hour earlier was located close by," he said.
"She was spoken to by Gardaí and she was detained at the scene.
"She can still be questioned up to 24 hours without charge... those Gardaí are hoping she will be available to them as early as today to be questioned.
"Certainly, the line of inquiry is that foul play was a factor in the boy's death and that he died of suffocation, possibly, or something similar".
Mr Lally said Gardaí are also working to establish if Matthew had been in the sea at some point before the alarm was raised.