Ellie Lawrenson's grandmother has told a court that she was responsible for the five-year-old's death after she was mauled to death by the family dog.
Ellie suffered severe head and neck injuries
Jackie Simpson, 45, was baby-sitting Ellie when she let the pit bull terrier into her house on Merseyside.
It attacked the child causing 72 injuries. Asked if she accepted blame, Ms Simpson said: "Yes, because I let the dog in."
Ms Simpson, from St Helens, denies manslaughter by gross negligence.
"If things had gone the way they should have that day I wouldn't have had the kids anyway. I opened the door and it's my fault. I never thought the dog would do anything to Ellie," Ms Simpson said.
Cross-examining her at Liverpool Crown Court, Neil Flewitt QC, said: "You let that child down, didn't you?"
"Yes," she answered.
Ms Simpson admitted consuming two bottles of wine and smoking 10 cannabis joints on the day of the attack.
Earlier she told the jury that the dog, a pit bull terrier called Reuben, had been kicked, punched and tormented by members of her family.
Ms Simpson said her son Kiel had once lashed out at Reuben shortly before it bit Ellie's aunt, Kelsey.
Speaking about the attack on Kelsey, the defendant said her son Kiel, 24 - who in April pleaded guilty to owning a dangerous dog - punched and kicked the animal 10 minutes before it bit her.
She said: "Kiel was in a mood and punched and kicked the dog. He then left the house, I had never seen him do that before. He punched him in the head and kicked him on his back leg, the dog yelped."
On other occasions, Ms Simpson said Kelsey herself had tormented the animal.
She denied that she had broken a family rule by allowing the dog inside her home where he attacked Ellie.
Ms Simpson said she had no reason to suspect any danger if the pit bull terrier was allowed inside.
She admitted that she knew Reuben was a powerful, banned dog. But she denied worrying whether St Helens Council would discover the banned dog in her home and said a vet told her son Kiel that Reuben needed behavioural classes.
Mr Flewitt asked her: "You have a strong, powerful dog you know is banned by the law - a dog that should have but wasn't getting behavioural classes - and you knew that in the summer of 2006?"
"Yes," she replied.
Mr Flewitt said if she considered Reuben's exceptional strength and previous attacks, she must "have realised it could have killed a five-year-old girl".
Ms Simpson replied: "I wouldn't have thought it could have done that to a baby it had grown up with."
The dog was later shot dead by police.
The case was adjourned until Friday, when lawyers will make their closing speeches.
It is thought the jury will retire to consider its verdict on Monday.