Just a few minutes before the start of yesterday's Children's Mass, some parents were still reassuring their children, "It won't happen again." Mothers stood in groups comparing the nightmares their children had suffered the night before.
One boy dreamt that the gunman jumped out of a suitcase in his bedroom and shot him in the head. Another girl's mother was worried that her eight-year-old daughter was completely unwilling to talk about the incident.
Some of the children had bounced back from the experience with less difficulty, one proclaiming to his friend, "Guess how much money I got yesterday."
While 25 children took a full part in the Mass two girls would not enter the church, fearing a repeat of Saturday's attack. Communion was brought out to them.
Eight-year-old Emer Flynn decided to make her communion yesterday, despite having had little sleep the night before. Her mother was concerned about the long-term effects the incident would have on the children.
"They're going to need some kind of counselling. It's going to be very difficult for them to get over it. It wasn't just one shot, there were several bangs. The screaming from the children was something terrible.
"Then there was a mad push to get into the room at the side of the church. Kids were tearing at each others' dresses and veils trying to get into the room, because they thought the gunman was firing at random."
The children were just 15 minutes away from making their First Communion on Saturday when the gunman opened fire in the church. The First Communicants had taken part in the Offertory procession during which they brought gifts symbolic of their work and play, including toys, homework books and drawings, to the altar.
The gunman entered the church from the main entrance at the back of the building, turned right, and walked behind the congregation, who were focusing on the altar. He walked down the right-hand aisle, passing a wall festooned with multi-coloured card board flowers which featured the First Communicants' photos at their centres.
Father Kevin McDonagh said eyewitness accounts described the gunman's approach as having "all the hallmarks of something quite premeditated. He took a studied professional approach. He was not the least bit disorientated."
Mr O'Toole received a gunshot wound in the lower back. The gunman then fired between three and five shots in the air, causing the children to panic.
Mr O'Toole was bleeding profusely but remained conscious. He was comforted on the floor of the church by worshippers and by the celebrant of the Mass, Father Terry Twohig.
Teachers and parents hugged the children, who were screaming, crying and shaking. Some of the children were reluctant to leave the church, convinced that there was a gunman waiting to shoot people coming out.
Father Kevin McDonagh arrived at the church almost immediately after the incident.
"The scene was one of pandemonium and chaos when I arrived. Four or five police cars and a helicopter arrived very quickly. People were milling out of the church and children were crying and shaking.
"Some of the female teachers were very upset. What came to mind immediately was the Dunblane incident. People were afraid it was a maniac who was embarked on a killing spree."
Before yesterday's Mass the principal of St Joseph's Junior School, Ms Maura Sheehy, promised the children there would be "another day with a special ceremony."
Father McDonagh, who celebrated the Mass, told the First Communicants: "We grown-ups - myself, teachers, parents - are very sorry. Sorry from the heart that your lovely, special joyful day was upset yesterday.
"Not that your parents, teachers, or priests were to blame, but as grown-ups we're all called upon to help you and love you and give you protection."