In Melbourne's north-west, two young girls rescued from a burning home in Sydenham have died in hospital, while their three-year-old step-brother remains in critical condition. The blaze, which started at the rear of the property, has prompted an ongoing investigation by the Arson and Explosives Squad to determine its cause and the whereabouts of the children's mother at the time. Meanwhile, in the Blue Mountains, two boys aged nine and eleven were found dead in their Faulconbridge home by their father, with their mother arrested and hospitalized under police guard for self-inflicted injuries. Police have launched a homicide investigation, suspecting a failed murder-suicide attempt, and confirmed no other suspects are being sought. Both incidents have deeply affected their respective communities, prompting calls for any additional information to be reported to authorities.