Convicted serial killer Beverley Allitt was a nurse in Grantham, Lincolnshire, when she started her deadly attacks on children.
Allitt's minimum jail term was confirmed at 30 years
During an eight-week period in early 1991 she killed, attempted to kill, or seriously harm 13 children in her care on the paediatric ward.
Allitt's first victim was Liam Taylor, aged seven weeks, who was the son of Joanne and Chris Taylor.
The baby boy, who was admitted to hospital with breathing difficulties, had a number of unexpected collapses on the ward while Allitt was the sole adult present.
The prosecution evidence was that it was impossible to determine the precise cause of his February 1991 death - whether it was the result of suffocation or the injection of a drug.
Claire Peck, who suffered from asthma, was admitted to hospital and collapsed when Allitt was alone with her.
Allitt is being held at Rampton Secure Hospital
Allitt was convicted of her murder after the jury heard prosecution evidence that the toddler had been injected with potassium and lignocaine in March 1991.
After hearing, the father of the 15-month-old David Peck, said: "I'm absolutely delighted with the outcome - and pleased for the other families as well.
"We can now put this behind us after 15 years. I couldn't ask for anything better."
Two-month-old Becky Phillips was killed and her twin sister, Katie, was left severely disabled.
Katie was awarded £2.13m by the Lincolnshire Health Authority in 1999 after an eight-year battle. She now suffers from partial paralysis and blindness.
Mother Sue Phillips (now Laccohee) said in a statement after the High Court hearing: "It is harder to think of a greater evil than a paediatric nurse deliberately killing her young charges.
"This is an evil for which her rehabilitation and return to the community should not be contemplated."
Timothy Hardwick, 11, was Allitt's last murder victim. He suffered from cerebral palsy and was admitted to the ward after having a seizure.
Allitt was said at her trial to have been suffering from the rare Munchausen Syndrome, in which sufferers harm themselves or others for attention.
High Court judge Mr Justice Burnton said he was satisfied that she was suffering from "an abnormality of mind" when she committed the offences.
Her trial heard of her intensely disturbed behaviour, including self-harming since childhood.
Allitt can apply to be freed in 2021.