Tracy Menhinick, 52, administered a non-prescribed medication, namely the laxative lactulose, which caused the child's development and mobility to be affected and led to him being admitted to hospital.

Menhinick, of Aberdeen, then consented to treatments, procedures and operations which she knew were unnecessary, "all to his permanent disfigurement, permanent impairment and to the danger of his life".

She was found guilty in February of wilfully ill-treating the child in a manner likely to cause him unnecessary suffering or injury to health on various occasions over the course of three years from 2014.

The ill-treatment happened when the boy - who cannot be named for legal reasons - was aged between three and six, at an address in Aberdeen, at Royal Aberdeen Children's Hospital, and elsewhere.

Judge Lady Drummond highlighted that a doctor during the trial described the boy as "emaciated" on his last admission to hospital.

The judge told Menhinick: "You had been an auxiliary nurse and knew what you were doing. You caused him to be in that state."

She added: "The doctors were baffled as to why despite all their intensive efforts to care and treat the child, the many tests and variations in treatments, he was not gaining weight and thriving.

"The level of laxatives he was being given were such that at times he would have floppy episodes when he became limp and had to be resuscitated."

Lady Drummond noted that the boy has suffered physical scarring.

The judge said: "Why anybody would want to inflict such severe harm and suffering, endangering the life of a young child on multiple occasions over a period of years is beyond understanding."

It was noted that Menhinick's actions were "likely to have had a negative impact" on the boy psychologically.

The judge stated: "Your ill-treatment of him has had a devastating impact on his life."

Menhinick was sentenced at the High Court in Glasgow on Tuesday after her case had been deferred for a psychiatric report.

Lady Drummond was earlier told by Menhinick's defence that she had a "package of mental health problems" which may have affected her culpability.

The judge noted that Menhinick rejects that she suffers from a factitious disorder imposed on self and imposed on another (previously Munchausen syndrome and Munchausen syndrome by proxy).

Menhinick, who appeared at court in a wheelchair, was said to now be bed-bound.

Lady Drummond accepted that Menhinick had suffered childhood trauma, but added: "The only appropriate disposal for such serious ill-treatment of a child over a three-year period with such serious consequences must be a significant period of imprisonment.

"That is to mark society's abhorrence of this conduct."