The mother of a two-month-old baby boy who remains in hospital after suffering injuries consistent with 'shaken baby syndrome' has spoken for the first time about what happened and expressed her fears about the child's medical prognosis.

In an interview with the Sunday Tribune, the infant's mother has told how she noticed a bruise on her son Devin's face 11 days ago and asked her fiance if anything had happened to the child the night before.

"I asked him if he touched the child to try and calm him down the night before; I was out. He said he did not know what had happened to him. I don't think he would have hurt him on purpose. If something did happen, I think it was an accident," said the 24-year-old European woman, who asked that her identity not be disclosed.

She said he was a caring father and had never attempted to harm their son before. The following morning, the young mother brought Devin to her GP after she noticed he was having a seizure down one side of his body. The doctor told her to go immediately to Temple Street Children's hospital.

"At the hospital, they gave him a CT scan and an MRI scan and told me he had brain swelling and bleeding behind his eye. He was admitted to the intensive care unit and they asked me all sorts of questions. I told the truth. I said I didn't know what had happened to him. I said maybe the child's father did something to him by accident but I did not know. I told them his father loves his son very much. We both do."

The infant has awoken in the past few days and is now drinking from a bottle. "The doctors do not know what brain damage he has suffered from this but the next few weeks will be very important. As far as I understand, there is some damage to the brain. I love my child so much. I don't know what I would do without him."

The young woman has met with social workers on a couple of occasions since his admittance to hospital. She has no family in Ireland and her parents are planning to come over when the baby's condition improves.

Detectives from Fitzgibbon Street garda station have launched a major investigation and have interviewed both the baby's parents, who live together in Dublin's north inner city.

Senior garda sources say there is little doubt that the baby was assaulted but say there were no witnesses to anything that might have occurred. A file is being prepared for the DPP, who will determine if any charges should be brought.