A mother injected a friend’s four-month-old baby with a huge overdose of insulin because she was jealous that she had a healthy daughter, a court heard yesterday.

Veronica Duncan, 41, an intensive care nurse whose own child had died just months earlier, engineered a situation in which she was alone with the baby after inviting the child’s mother out for coffee. She then injected her repeatedly with the hormone. Later she turned up at the hospital where the child was fighting for her life.

Duncan, who has been detained in a psychiatric hospital since being charged with attempted murder earlier this year, yesterday pleaded guilty to a reduced charge of assaulting the baby and endangering her life.

Had it not been for the quick thinking of a doctor at the Borders General Hospital, the child would almost certainly have died, the High Court in Edinburgh was told.

The former nurse sobbed uncontrollably in the dock as Alastair Brown, for the prosecution, described how she had called at the child’s family home in a village in Peeblesshire and invited her mother to go to a coffee morning.

After arriving at the house one morning in March she offered to dress the baby while the mother — who has not been named — changed to go out. Mr Brown said: “It appears that it was at this point that Duncan injected her with insulin.”

The women then went to the coffee morning before they parted company and the victim’s mother took her daughter and her other child to a swimming lesson. It was only when the baby kept falling asleep and her eyes would not focus that her mother became concerned and spoke to a family doctor who was also at the pool, the court was told.

Once at hospital a doctor “undoubtedly saved the baby’s life” by instructing that dextrose be given to the child after she was found to have low blood-sugar levels, the court was told.

The baby was found to be “drowsy, floppy and unresponsive”, with three red spots in a triangle shape near her navel. It was later found that this was where she had been injected.

Duncan even turned up at the hospital where the baby was fighting for survival, but did not say a word about what she had done, the court was told.

Duncan had access to insulin through her job in the intensive care department at Edinburgh Royal Infirmary, where she was registered as a general nurse, Mr Brown said.

Although the baby survived, Mr Brown said that she now faced an uncertain future. “She suffered a severe insult to her brain so it is difficult to say whether there will be any long-term problems,” he said. Since then the baby’s parents had wrapped the baby in “triple cotton wool” and had become “extremely protective”.

They had been questioned by police following the overdose and child protection measures were put in place that barred them from taking their daughter home. It was not until several weeks after the incident that Duncan’s home was searched and a box containing a syringe and insulin was found. She later admitted that she had taken a syringe to the child’s family home and injected the baby.

The court heard that Duncan was suffering from an “abnormal grief reaction”. Her own 16-month-old daughter had died in May last year from a complication after catching chickenpox. Her husband had blamed her for their daughter’s death, the court was told. Mr Brown said: “She was asked for an explanation as to why she had done this and could offer no explanation other than she was jealous and envious of the child’s mother and the fact she had a healthy baby daughter.”

Sentencing was deferred for background reports.

Times Recommends

• In Margot Fonteyn's footsteps
• Forget beautiful people, let's have wonky Brits
• Fundamentalist brew: faith and power