I'll start it off with a vindictive killer nanny from 1871

https://trove.nla.gov.au/newspaper/article/135806237?#

Extraordinary Child Murder.
On May 11 a shocking murder was committed at a beautiful farm residence on the summit of one of the Buckinghamshire hills, commanding a fine view of one of the beautiful sylvan landscapes for which the county is famous. The scene of the tragedy was a large handseme house at Steeple Claydon, a little hamlet on the Oxford and Bletchley Railway. At this quiet retreat a little
fellow scarcely five years of age, whose parents are far away in India, was brutally murdered by his own nurse.

From what transpired at the inquest, it appears that the deceased, whose name was Bruce Donald Logan, was the son of parents
residing in India. He, with his younger brother and sister, had been under the care of Miss Macdonald since last autumn. He always
enjoyed good health, and she saw him about half past nine o'clock on the night prior to the murder asleep in bed, to all appearances in his accustomed health. Catherine Muir, the nurse, had been more than three years in the service of the parents, having lived with them in Devonshire, and she seemed at first to be always kind and
attached to the children. Mrs Logan, when she left her children in her charge, appeared to have every confidence in the nurse, and so far from giving any caution about her, she evidently had full confidence in her.

Nevertheless, the nurse had once, in witness's opinion, unduly chastised the deceased for spilling some water, and Ethel Mary Logan, the little sister, had made complaints of being whipped, in consequence of which representations were made to the friends of the children, and it was arranged that the nurse should leave. Witness, however, told her that she was not discharged from Mr Logan's service, who would have to be communicated with in India, but simply that she could no longer remain in the house.

On May 11 she directed a servant to go up to the nursery and tell nurse to send the two little boys down to prayers, the little girl having already made her appearance, The servant returned with the information that the nurse was not in the nursery, and that the little boys were both in bed. Witness herself then went up, when she found little 'Rossy,' the brother of the deceased, sitting up in bed. He said "Nanny," meaning the nurse, "is very sick, and so is Brucy."
Glancing at the bed in which deceased slept, she saw him lying with the pillow stained with blood, while the nurse was crouched down on the floor behind the washandstand. She immediately ran
to the stairs, and called out, "For God's sake, Charles, come up !" appealing to the Rev. C. Plumtre, who was on a visit at her house, and who immediately obeyed the summons.

Ann Ladiman stated that she was employed at Miss MacDonald's as a day servant to attend to the nursery On the morning in question, about half past seven o'clock, she took up hot water as usual, and found nurse sleeping with the youngest boy and the little girl. Bruce was asleep in another bed. She returned downstairs, swept the nursery and went back to the bedroom. She found the little girl sitting on the floor, but neither nurse nor boys were up.

Nurse asked if Bruce was up. She looked and saw that he was, when nurse asked for a knife and witness offered her a penknife, when she said, "No, not that, a large one," and witness went downstairs again and fetched a table knife. Nurse then directed her to take Ethel, the little girl, down and to comb her hair, but to be careful not to make a noise in shutting the door, as she wanted Rossy to sleep a little longer. She had occasionally fetched brandy for nurse. On may 9 she bought 1s worth for her, and on the next day a bottle, for which she paid 6d.

Mr Benjamin Shephard, superintendant in the Bucks constabulary, spoke to being called to the house, when he found Mr. Plumtre in the room, and the woman crouching down. He went to her
and saw that her hands and feet were smeared with blood. She had only her chemise on, which was also stained with blood. He raised her and found under her the table knife produced wet with blood. In the room he found also a half consumed bottle of brandy and a penknife. The woman repeated several times that Miss Macdonald had been kind to her, but Miss Fanny Macdonald had not.


The coroner having briefly summed up, remarking that there could be no doubt the nurse inflicted the injury which caused death, the jury at once and without a moment's deliberation returned a
verdict of "Wilful murder against Catherine Muir." The prisoner has undergone an examination before the magistrates at Steeple Claydon and has been committed for trial on the capital
charge.