When baby Joshua Tighe's mother arrived at the house where the six-month-old had died, she turned to the boy's father - who is on trial accused of the infant's murder - and asked him: "What have you done?", a court has heard.
Yesterday, the Central Criminal Court trial also heard from a paediatrician who said a baby of Joshua's age could not have formed or swallowed the wad of tissue that a pathologist found in the baby's throat and the prosecution alleges caused his death.
The paediatrician also told the jury she did not believe it would be possible for the wad to become lodged as it did by efforts to remove it.
John Tighe (40), of Lavallyroe, Ballyhaunis, Co Mayo, has pleaded not guilty murdering Joshua Sussbier Tighe at his home on June 1, 2013.
Yesterday, Sergeant Alan Ryan told prosecuting counsel Paul Murray SC that he arrived at Mr Tighe's home shortly after Joshua had been declared dead.
Mr Tighe was "crying uncontrollably" and told Sgt Ryan that he had changed the baby's nappy, went to the toilet and when he returned the baby had difficulty breathing.
The baby's mother, Natasha Sussbier arrived shortly afterwards. Sgt Ryan recalled she was distressed and said to Mr Tighe: "What happened? What have you done?"
Mr Tighe repeated what he had said to Sgt Ryan, telling her the child must have swallowed something. Sgt Ryan said that Ms Sussbier noticed blood in various places - the court has heard there was blood on the baby's clothes, Mr Tighe's pyjamas and on the floor.
When Ms Sussbier asked about the blood, Mr Tighe told her that while he was attempting to bring up the obstruction he put his finger in the baby's mouth and this caused Joshua to bring up blood.
Under cross-examination, Sgt Ryan told Desmond Dockery SC, defending, that before Ms Sussbier arrived, Mr Tighe told him, "she is going to kill me," referring to Ms Sussbier.
Sgt Ryan took a voluntary statement from Mr Tighe the next day and said he was "extremely forthcoming".
Mr Tighe said he had been changing Joshua's nappy and there were tissues and wipes loose by the baby's head but when he returned from the toilet the baby was "a bit glazed looking", was having difficulty breathing and had gone blue.
He phoned the HSE's emergency service, who told him to hit the baby on the back, but Joshua died before a doctor arrived. The trial continues.