Toronto police allege a 45-year-old man poisoned a three-year-old child who died after eating cereal laced with an unnamed substance.
They say they began an investigation on March 7 after the death of a child at a sleepover.
Police allege the man got hold of a controlled substance from his work and put it on the cereal of two children.
Both children needed hospitalization, one child died and the other recovered after a lengthy hospital stay.
Francis Ngugi, 45, of Toronto, is charged with criminal negligence causing death, two counts of administer noxious substance to endanger life and two counts of unlawfully causing bodily harm.
He appeared in court on Sunday.