It was one of the most dramatic – and revealing – moments of Lucy Letby’s ten-month criminal trial.From behind a screen, one of her former work colleagues, a paediatrican, gave his name to the jury and, at the sound of his voice, the former neonatal nurse suddenly became tearful, standing up abruptly as if to try to leave the glass-panelled dock.This was the first time – and one of the only times – that Letby, 34, couldn’t hold back or hide her emotions during the case.The married doctor, who worked with Letby at the Countess of Chester Hospital, was described by prosecutors as her ‘boyfriend’ – a description he has always refused to comment on – and the court heard how over a period of just three months in 2016 the pair swapped more than 1,300 flirty messages over Facebook, often late at night.Later, they met for walks and meals and went on day trips to London together in their free time away from work.Letby denied having an affair or being in love with the medic, although a note discovered at her home by police following her arrest perhaps betrayed her true feelings.‘My best friend … I loved you and I think you knew that … I wanted you to stand by me but you didn’t,’ Letby had written on the scrap of paper, next to the doctor’s name which was surrounded by love heart doodles. Her tears in the dock certainly left no one watching – as I was – in Court Seven at Manchester Crown Court back in February last year in any doubt that his decision to give evidence against her cut deep.This week that paediatrician, who cannot be named for legal reasons and is known only as Dr U, made a much-anticipated appearance before the public inquiry that is investigating Letby’s crimes. Lucy Letby went on day trips with ‘Dr U’, who admitted to a public inquiry this week to standing by the killer nurse for months after she was moved off the neonatal unit in July 2016, and also to trying to help salvage her derailed careerIn evidence made via audio feed that will shock the families of her victims, he not only admitted to standing by the killer nurse for months after she was moved off the neonatal unit in July 2016 and placed into an administrative role, but also to trying to help salvage her derailed career.He claimed he had no knowledge of his consultant colleagues’ suspicions about Letby and, in September 2016, he was telling Letby in messages ‘you are still the best neonatal nurse I have ever worked with’, supporting her in her grievance against the hospital trust rather than questioning her role in the deaths of the babies in her care.Even after leaving the Countess in September 2016 to work as a locum consultant at Liverpool’s Alder Hey Children’s Hospital, he was still looking out for Letby.In December 2016, six months after she was moved off the unit where they had worked together, he wrote to his new bosses, appealing for Letby to be allowed to make ad hoc visits under his supervision, to watch operations on babies and attend outpatient clinics, team meetings and other observational sessions.Those visits, in March and April 2017, included a ‘roadshow’ information session relating to insulin pumps – the substance Letby used to try to kill two baby boys – and took place after a senior manager at the Countess, who knew Letby was suspected of causing harm, sent a letter of approval to Alder Hey. It apparently made no mention of why she was not working as a nurse in Chester, albeit stipulating that she must have no direct contact with patients and should be supervised at all times.Dr U told the inquiry his ‘understanding’ was that Letby was still having some patient contact at the Countess, by attending clinics in the obstetrics and gynaecology department at that time, and that she had simply been moved into the clerical role for retraining.He insisted he simply wanted to help her with her professional development. But the criminal trial heard that the couple continued to be very close in the spring and summer of 2017, meeting up five times in May and June, when they visited Hartford, a small town around 16 miles outside Chester, and Cheshire Oaks shopping centre.They also had a meal at Hickory’s, an American-themed restaurant by the River Dee in Chester, and met for coffee at Starbucks, before going on a day trip to the capital together.Dr U insisted to the inquiry this week that he had been ‘misled and maybe manipulated’ by Letby, who had persuaded him to give her information and pass on confidential emails about babies he later learnt she had attacked, on the pretence that she was struggling with her mental health.He said she told him she was having trouble sleeping and was anxious, so he shared the information to try to reassure her.Now, with hindsight, he said it ‘feels like a mistake’.‘It is something I have considered on a daily basis for the last six to eight years,’ he added.During Letby’s trial, prosecutor Nick Johnson KC suggested Letby was so infatuated with the father-of-two that she attacked and murdered at least four of her victims knowing he would be the one crash-bleeped to come and help.She created the ‘crisis situations’ because she wanted to get his attention, to work with him so they could try to save the babies together, Mr Johnson said. It also gave her something to talk to the older doctor – who is 17 years her senior – about afterwards. The paediatrician even provided a shoulder for Letby to cry on and comforted her, telling her what a good nurse she was when she feigned upset after murdering two brothers – identical triplets – on consecutive shifts, in June 2016.Dr U told the inquiry he was unaware that consultants at the hospital were suspicious of Letby and has since regretted supporting her in her grievance against the hospital, which she launched when she was moved off frontline nursing immediately after the two triplets died.The trial heard that Dr U and Letby’s friendship had begun just a few weeks earlier, on June 2, 2016, when he messaged her on Facebook asking for a ‘favour’. It prompted Letby to WhatsApp one of her close nursing friends while she was working a night shift that same evening – just hours before she attacked and tried to kill Baby N, a premature baby with haemophilia.She wrote: ‘Had strange message from (Dr U) earlier.’Her friend replied jokingly: ‘Did u? Saying what? Go commando?’Letby said: ‘Asking when I was working next week as wants to talk to me about something, has a favour to ask..?’Her friend added: ‘Think he likes u too. Hmm did u not ask what it was?’Letby said: ‘No just said when I was working and he said wants my opinion on something. Hmm… Do you think he’s being odd?’Her friend replied: ‘Thought as flirty as u.’Letby said: ‘Shut up! I don’t flirt with him! Certainly don’t fancy him ha ha just nice guy.’She later claimed in cross-examination she didn’t know what ‘go commando’, a phrase used to refer to wearing no underwear, meant.In other messages sent on another shift two weeks later, after Letby allegedly tried to murder Baby N twice more on the same day, the pair discussed her upcoming annual leave and holidays in Cockington, Devon.Letby described Dr U as a ‘sweetie’ when he bought her chocolate to cheer her up and offered her his car so she didn’t have to walk home from work after the stressful shift, during which Baby N nearly died and had to be transferred to a more specialist unit.In one message, sent two-and-a-half hours after the second alleged attack on Baby N, Letby told Dr U about the baby’s medical problems, before adding: ‘Sat having a quiet moment and want to cry.’He replied: ‘Oh Lucy, poor little thing. And you? Are you ok?‘Have a cry, you’ll feel better for it I’m sure.‘You’re welcome to take my car home if you’re too tired to walk. I’ll sort out picking it up in the morning.‘So sorry you’ve had a rubbish day.’ After discussing the baby’s condition, Dr U added: ‘I am sure he has had the best care possible and you will have done everything you could for him.’Rachel Langdale KC, counsel to the inquiry, asked Dr U whether it had been appropriate for him to talk about Baby N with Letby at this time.Dr U said: ‘In hindsight, no. Looking at the content of the messages here, I’ve shared too much. It’s common to give updates on how patients are without naming them, without giving lots of clinical detail to help the recipient understand where that patient is up to. I gave, at the time, details that I thought were helpful but I see now that that probably wasn’t the case.’The inquiry has been told that Baby N’s parents were ‘horrified’ to learn that their son had been discussed by the pair over Facebook on their private mobile phones.His mother accused Dr U of ‘blatantly’ breaching her son’s patient confidentiality in the messages, some of which even included his full name. Dr U agreed Baby N’s parents would likely find the messages ‘upsetting’, but insisted there had been ‘no malice’ in them.However, the inquiry heard Baby N’s mother has lodged a formal complaint about Dr U with the hospital where he now works. An investigation into his conduct is ongoing.Dr U was also on duty when Letby murdered the two triplets, known as Baby O and Baby P, on consecutive shifts around a week later on June 23 and June 24, and when she allegedly attacked the last infant, Baby Q, on June 25. The jury failed to reach a verdict in his case.Later that night, Letby messaged Dr U, ‘Do I need to be worried?’ when she discovered one of the consultants, Dr John Gibbs, had been asking about his care.Dr U told the inquiry: ‘I didn’t know exactly what she was worried about but I think having looked after the two babies on consecutive days she was concerned that she would be thought to be responsible for the deaths and, as I didn’t know of the number of preceding deaths, it was a reassuring “no”.‘I was aware of her mental health problems and the amount of anxiety that she had.’ Letby when she was working at the Countess of Chester Hospital’s neonatal unit After two trials, Letby was convicted of seven murders and seven attempted murders of infantsIn fact, he was so convinced of Letby’s nursing capabilities, he messaged back: ‘You are one of a few nurses across the region (I’ve worked pretty much everywhere) that I would trust with my own children.’ He also offered to write her a ‘statement’ if anyone suggested the care she had provided was ‘not good enough’ or inadequate, such was his faith in her.Miss Langdale said: ‘She was worried if people were asking questions about it, wasn’t she?’Dr U said: ‘In hindsight, yes, obviously.’Miss Langdale said: ‘And at the time you mistook that for what?’Dr U said: ‘Anxiety.’Miss Langdale asked Dr U about a meeting he attended with consultants about the triplets’ deaths in which Letby’s link to them was discussed. But Dr U claimed he left before she was mentioned and said he didn’t remember anyone raising concerns about her.However, he admitted it had been an ‘error’ for him to forward Letby a confidential email from neonatal lead Dr Stephen Brearey, in which he indicated Baby O and P’s deaths would be investigated at inquests.Miss Langdale asked: ‘Why did you send that email to her?’Dr U replied: ‘She gave me the impression she was very upset… I was basically trying to give her some insight into what was going on.’ He admitted that, in retrospect, Letby appeared to be ‘panicking’ about the events and her role in them.Miss Langdale said: ‘And needing information from you about babies and how they might have died?’Dr U said: ‘It felt like a supportive gesture. That now feels like a mistake. It is something I have considered on a daily basis for the last six to eight years.‘I have become aware that I was not aware of the full clinical picture and I provided support by being misled and maybe manipulated, and for that I’m really sorry that things have come to an end as they have. I have a lot of regrets over how that period of time took place.’Eventually, Dr U turned his back on Letby and their friendship ‘fizzled out’ at the beginning of 2018, around six months before her first arrest.Although they both always denied having an affair, questions still remain about the full extent of their relationship.