The incident happened on July 25, when Danah McKinnon-Bozek, who was eight months pregnant, and her two young daughters were hit by a car that suddenly reversed and slammed into the front entrance of the store.
The collision killed Addison Hall, 6, and injured her mother and three-year-old sister Miah Bozek.
Another daughter, Rhiannon Bozek, was delivered by emergency C-section. The newborn died Aug. 1.
Police announced on Aug. 8 that Ruth Burger, 65, of London, had been charged with two counts of criminal negligence causing bodily harm related to the mother and younger girl and one count of criminal negligence causing death related to the death of the six-year-old.
At the time, police said they had no legal grounds for a charge in connection with the newborn's death.
"The definition of the Criminal Code has some stipulations that a person becomes a person, essentially, when it is born from its mother in a living state,'' said London police Sgt. Amanda Pfeffer.
But after additional consultation with the local Crown attorney’s office in a "rather fluid" investigation, Pfeffer now says Burger has also been charged with criminal negligence causing death in connection with the infant's death.
"After a review of the evidence to date by the Crown attorney we had a consultation and determined that it would be appropriate at this time to lay that charge," said Pfeffer, who heads the London force's traffic unit.
"It's not a unique situation that an additional charge would be laid or that a different charge may be laid that may be more appropriate given the circumstances," she said.
"There was a comparison of the evidence as it relates to the legislation and it was determined that at this point in time it would be appropriate to lay that additional charge."
Pfeffer declined to discuss the evidence — including "medical evidence" — saying the matter is now before the courts.
Two other people suffered minor injuries in the crash, as did the car's driver.
Burger's next scheduled court date is Oct. 21.