York Regional Police issued a news release yesterday indicating that police had been called to a Newmarket home on Thursday afternoon.
A two-year-old boy was not breathing when police arrived. He was rushed to hospital, where he was pronounced dead.
Police have not publicly identified the cause of the boy's death.
The boy's father was arrested Saturday.
Mario Wint, 29, faces a count of second-degree murder.
During his court appearance on Sunday, Wint wore a grey hoodie that said "Xmas is cancelled."
He will appear in court again on Wednesday.
On Sunday, investigators remained at Wint's home. A police cruiser was parked at the curb.