The police said that Letby was a prolific writer. People who keep diaries and journals do tend to pour out their true feelings, not expecting any third party to ever read their jottings, which are more of a reference for themselves. Letby jotted down in her diary - which macabrely is in shades of girly lilac and pink - by the dates of death of her victims, their initials.
Key medical notes, one of which was proven to have been retrieved from a bin for confidential material of how one of her victims desaturated to death. These notes were kept in a supermarket bag under her bed. People file their documents according to category, importance and sentimental value. Given her victims did die from unnatural causes (synthetic insulin, overfeeding, brutally dislodged feeding tubes, injections of air, etc) and their notes all kept together in a special place of their own, they appear to have had some value for Letby. Planigale thinks it could be for feelings of guilt rather than as trophies with the sentimental value to relive the incidents again and the addictive rush of adrenaline that accompanies highly risky behaviour. Letby writes a fair bit about her crush on the married doctor and he leads her on in return. After Letby killed one twin, this married doctor offered her the use of his car to drive home, as they were close enough to use each other's car. Letby mentions the names of her cats and her nephews, as well as her parents. She calls the four doctors who wants her off the wards, 'BASTARDS'. ISTM she wasn't writing for the benefit of a third party but adds occasional disclaimers just in case, for plausible denial she meant what she said about 'I did this'.
Her father was present when the police arrived to arrest her. Her bedroom as largely designed by Dad seemed to be as if for a nine-year-old.
Mr. Letby was present at Letby's disciplinary hearings; he became friendly with the Head of the NHS Trust and Letby moved in with her parents after arrest and took the bag of victim documents with her to her new address.
ISTM Letby suffered arrested emotional development, having needed thyroid therapy when young and thus had overbearing stifling parents keen to cushion their only child, still going on holiday with them every year as a grown adult. So, on an emotional level, she was like a young child that is keen to boss around and control say, her pet animals, without understanding their being sentient animals and thus not so much knowingly cruel but more not mature or developed enough to have empathy towards the objects of her bullying behaviour. Plus, having Mum and Dad being able to see no wrong in their dear 'yes, my darling' daughter. However, on an intellectual level, Letby surely knew her treatment of the neonatal babies was wrong.
She was in a fix, though, because she had the backing of her authoritarian father, the NHS Trust Boss and the nurses union against the hospital doctors. They were even made to apologise to her by her father. Such was Dad's belief that Letby could do no wrong. So, IMV Letby wrote all of that stuff confessing she killed them because on one level she wanted to be caught and stopped. Hence the escalation in killings and attempted killings because on a subconscious level she was saying, look, isn't it obvious???!!! These are all twins, triplets, can't just be coincidence. Her affirmation in court after the last guilty verdict of, 'I am innocent', IMV, was really for the benefit of her parents whom she didn't want to disappoint because she knew in their eyes they idolised her.
So one could say the notes confessing guilt were cries for help, albeit for self-tranqulisation purposes.
The other reward she got from her behaviour was the attention of the married doctor who plied heaps of sympathy on her and reassurance that everyone thought she was a great nurse and highly competent. It was all just incredibly bad luck the deaths should happen to her. And the thing is, the nursing head believed Letby.