Baby still critical after mall car attack

A three-month-old baby is still critical after being injured when hit by the car that struck pedestrians in Melbourne's Bourke St mall.

The Royal Children's Hospital says the baby and two other children - a two-year-old in a serious condition and a nine-year-old in a stable condition - remain at the hospital on Saturday.

Four people were killed in the incident on Friday afternoon when a driver with history of violence and drug and mental health issues mowed down pedestrians.