Ross Murphy was admitted to Wexford General Hospital last weekend. He was later transferred to Our Lady’s Hospital in Crumlin where he died on Tuesday morning.
It is believed the baby, who lived with his mother and her partner in Gorey, Co Wexford, had little visible bruising to his body. But a preliminary examination found he had suffered serious and unexplained internal injuries.
Gardaí said they are treating the incident as “an unexplained death.”
Gorey Supt John Roche said the matter was reported to them on Tuesday morning, just after the boy died.
“We were alerted after a report went to the Dublin county coroner. We are awaiting the full post mortem results before we decide on the future status of our investigation,” he said.
Gardaí visited Wexford General Hospital where they spoke to a number of staff including the doctor who treated the baby.
They are also speaking to staff at Our Lady’s Hospital who raised the alarm and contacted gardaí. Neither the hospital nor the HSE Eastern Region would comment on the matter.
It is believed that state pathologist Dr Marie Cassidy may want to examine the baby’s remains further before reaching a conclusive cause of death.
Gardaí have not yet received her preliminary post mortem results.