A teen girl accused of killing a six-week-old baby boy had been invited into the family's home, says the boy's grandfather, after family members met the girl in downtown Saskatoon.

The grandfather told reporters outside court that his family did not know the accused killer, and his daughters had just met her downtown over the weekend.

"She ended up at the house. The girls met her downtown, she like, had nowhere to go. I raised my children to respect, to help out people in need," he said.

The provincial government told CBC the teen girl walked away from custody at Kilburn Hall Youth Centre, a youth detention centre in Saskatoon's Buena Vista neighbourhood, early Saturday morning.

Timeline

The girl ran away from Kilburn Hall at 12:45 a.m. CST on Saturday.

Saskatoon police were called about the escapee at 12:48 a.m.

A baby boy was found injured in the 200 block of Waterloo Crescent around 7 a.m. Sunday.

Police laid second-degree murder charge against a 16-year-old girl Sunday evening.

Police confirmed that the girl charged in the death is not related to the baby.

The baby was found injured early Sunday morning in Saskatoon's College Park neighbourhood after a report was made to police. He was taken to hospital where police said he died of his injuries.

Officers didn't say how the baby was injured.

The teen, who cannot be named due to her age, had been staying at the Kilburn Hall detention facility in open custody, meaning that she could be charged if she left.

"The doors are open on the open custody side, and the offenders, if they choose to, are able to leave. Now once they've left, they are guilty of committing another offence," said Drew Wilby, executive director of the Ministry of Justice.

The girl appeared in court today, where an additional charge was added for escape from lawful custody.

Court appearance on 2nd-degree murder charge

Yesterday the teen made her first court appearance for the second-degree murder charge.

Court documents showed the girl is also charged with breaching the terms of an outstanding sentence by failing to keep the peace and consuming drugs and alcohol.

The teen had pleaded guilty in North Battleford provincial court on Dec. 22 to five other unrelated charges.

They include: breaking and entering, causing a fire, assault causing bodily harm, assault with a weapon and theft while armed with a tire iron.

She was in the midst of serving her previous sentence, which included open custody for 10 months followed by five months of community supervision and one year of probation.

The teen returns to court on the second-degree murder charge on July 11.