Laura Castle, 38, made the confession as one-year-old Leiland-James Corkill was on a life-support machine in hospital with catastrophic head injuries, Preston Crown Court heard.
The youngster had been living with his prospective adoptive parents Castle and her husband, Scott, 35, when emergency services were called to their home in Barrow-in-Furness on January 6 last year.
Laura Castle reported Leiland-James had fallen from a sofa while she was in the kitchen but medics at Liverpool’s Alder Hey Children’s Hospital raised concerns the injuries did not match her account.
She has since pleaded guilty to the manslaughter of Leiland-James, who lived with her for less than five months, but denies murder and child cruelty. Scott Castle has pleaded not guilty to causing or allowing the death of Leiland-James and also to child cruelty.
Jurors were told the couple had undergone a rigorous process by Cumbria County Council in being allowed to look after Leiland-James, who was taken into care at birth.
This process included “therapeutic parenting sessions” in which prospective adopters were taught how to be more nurturing and never to use corporal punishment.
On Tuesday, Penny Hindle, a social worker of 35 years’ experience, said she phoned Castle before the baby’s life-support was switched off on January 7.
She said: “I said to Laura that I had been advised that Leiland-James’s injuries were not consistent with her account.
“She was very upset. She said she had previously tapped or slapped Leiland-James.
“I was really shocked that given the emphasis on not hurting, assaulting, smacking, disciplining children in a physical way, that she was saying that was what she had been doing.
“Leiland-James was only a baby. He had just had his first birthday.
“I was really shocked that she had used force.”
The court heard last week a colleague of Mrs Hindle voiced her concerns that Laura Castle stated during a home visit in November 2020 she did not love Leiland-James.
Laura Castle went on to tell Mrs Hindle that she felt the youngster did not like them. A ‘looked after child’ review followed in which Mrs Hindle said she could not support a permanent adoption application from the Castles.
The social worker said the Castles accepted the decision and more therapeutic work took place at their home on December 16.
She said: “It was not totally negative. Scott Castle and Laura Castle both engaged well. Leiland-James was there. But they did have a lack of joy in in everything that he seemed to do.
“Some of their responses were negative and they were struggling to bond with him but they weren’t asking to remove him because they couldn’t go on.”
Laura Castle explained her family loved the boy so he was ‘not going anywhere’, she told the court. Mrs Hindle went on: “My reaction was that in itself is not a good enough reason to adopt a child.
“I was not convinced the adoption would hold.”