When infants started dying at England’s Countess of Chester Hospital in June 2015, neonatal nurse Lucy Letby was suspected from the start. Despite concerns raised by staff members, Letby continued to work at the hospital, targeting 17 newborns in her care within the span of a year. Following the suspicious deaths of two triplets, she was finally removed from her duties but remained in an administrative role until her arrest in July 2018. Letby, whose crimes are explored in Netflix’s new documentary, The Investigation of Lucy Letby, was eventually convicted of murdering seven babies and attempting to murder seven others. Now serving 15 life sentences with no possibility for parole, the 36-year-old is considered one of Britain’s most prolific serial killers. But sadly, her case is far from unique.…