LUCY LETBY tried to kill a baby hours after she helped make a banner to mark the girl becoming 100 days old, a court heard.

The youngster reached the milestone after she was born “very, very prematurely”, weighing only 535 grammes (1lb 2oz).

Doctors at Wirral’s Arrowe Park Hospital gave the girl a 5% chance of survival but she stabilised and months later was well enough to be transferred to the Countess of Chester Hospital.

Weeks later, on the evening of September 6, 2015, nursing staff on the neonatal unit, including Letby, made a party banner to prepare to celebrate the baby’s 100th day of life. A cake had also been brought in by a colleague to mark the occasion, Manchester Crown Court heard.

The parents had gone home but received a call in the early hours of the next morning to say their daughter had vomited.

Medics noted the baby, referred to as Child G, had projectile vomited at about 2am and her abdomen appeared “purple and distended”.

Her oxygen levels dropped and she stopped breathing several times over the next few hours before she responded to breathing support on ventilation.

The Crown says Letby overfed Child G with milk through a nasogastric tube or injected air into the same tube.

On the afternoon of September 7 she messaged an on-duty colleague, who cannot be identified for legal reasons, to ask if Child G was going to be transferred from the Countess of Chester.

The colleague said the girl was “improving a bit now” but noted that her leg and arm “both went white”.

Letby replied: “Not well at all, is she. Poor parents.”

She later messaged: “How are parents?”

The colleague said: “Devastated but determined she’ll get through ‘as always’. Thought that if she got to 100 then they would feel confident she’d be fine.”

Letby said: “Awful isn’t it. We’d all been sat at desk at start of the shift making banner.”

The defendant later told her colleague: “Needs to go out.”

The colleague replied: “Too sick to move.”

Letby said: “Oh no. Any idea what’s caused it?”

The colleague said: “Nope. Just seems to be a circ (circulatory) collapse, chest seems clear.”

Letby responded: “Hmmm. What can cause that? Is it that she’s been an extreme prem who had long term inotrope and vent dependency and now she’s older and doing more for herself and it just takes a little bug or something to tip her over as no reserves and chronic lung etc.”

Her fellow nurse said: “We are going with sepsis…and yes to no reserves, she looks grim.”

The court heard that Letby visited the unit briefly later that evening.

She later messaged her colleague – who had finished her shift – saying: “She looks awful doesn’t she.”

Her colleague replied: “Yeah. Going to APH (Arrowe Park Hospital) …So no better. Damn. I have a bad feeling. At least they know APH.”

Letby said: “Not looking good but yes least going to where she is known. Just hope they get here there.”

Her colleague said: “Hmmmmm not sure they will.”

Letby said: “On today of all days.”

Her colleague replied: “Yup poor parents.”

Letby said: “Yeah she’s declining bit by bit.”

Child G was transferred at 3am on September 8 to Arrowe Park, where she recovered and was moved back to the Countess of Chester more than a week later, the court heard.

The Crown says Letby made two more attempts to murder Child G on September 21.

Jurors were told Child G now has quadriplegic cerebral palsy and requires round-the-clock care.

Letby, originally from Hereford, denies murdering seven babies and the attempted murders of 10 others between June 2015 and June 2016.

The trial continues of Friday, December 2.