A senior doctor warned that the neonatal unit where Lucy Letby worked was chaotic and unsafe for patients, according to the Sunday Times. The paper says that paediatrician Dr Alison Timmis wrote to Tony Chambers, then chief executive at the Countess of Chester Hospital, in December 2015 saying staff were “chronically overworked” and that “when things snap, the casualties will either be children’s lives or the mental and physical health of our staff”. It adds that Letby would often volunteer to plug staffing gaps, particularly at night, when she could use the opportunity of being alone with babies to attack and kill them.