Sandra Higgins, aged 34, also said she cared for the baby girl like she was one of her own children.
Ms Higgins, of The Beeches, Drumgola Wood, Cavan town, has pleaded not guilty to intentionally or recklessly causing serious harm to the baby at her home on March 28, 2012.
On day two of the trial, Det Garda Linda Harkin told Sean Gillane SC, prosecuting, that Ms Higgins was arrested and interviewed on April 13, 2012.
The registered child-minder told gardaí she was born in Enniskillen, Co Fermanagh, but had moved to Cavan and studied practical childcare in Dublin.
She started minding the baby from June 2011 and said she treated her “like one of my own”. She said she had a good relationship with the mother.
She said the child’s first walk was on February 27 and after this there were a number of falls and bumps.
She said in March the baby was sick and was running a temperature and was sleeping a lot. On the date of the alleged assault the baby was better than the day before but was very quiet.
She said that morning they played for a while and the infant had a nap. The infant also had a sleep in the afternoon and then Ms Higgins said she woke her and placed her down on the floor in the playroom.
She told gardaí: “Her cheeks were flushed on waking. She went very quiet. She sat like she was in a trance.
“She went forward and back. She fell forward herself. She went on to her side and I remember she went on to her tummy. Her whole body was jerking.
“She was jerking all over the floor. I remember pushing toys out of the way. She started to get sick.”
She said the infant’s body was going cold and limp. She drove the infant to Cavan General Hospital.
Asked about previous bumps and bruises the infant had received while in her care, Ms Higgins told gardaí: “I didn’t assault [her]. She had falls. She had a seizure. She was never assaulted.”
She admitted she only filled out an incident report form in relation to a number of falls after the infant had been hospitalised.
She admitted failing to keep some records properly but denied creating records. She denied making additions to the childminding diary.
Garda photographs of bruises to the infant’s head and body were described to the court by consultant paediatrician Dr Alan Finan. The child had “extensive bruising all over her body”.
The trial at Dublin Circuit Criminal Court continues before Judge Patricia Ryan and a jury of eight men and four women. There is a court order prohibiting publication of the child’s name.