The man whose two young girls froze to death on a Saskatchewan First Nation reserve is devastated by the loss and knows he did wrong, his sister says.

"It'll probably take him a long time to actually forgive himself," Bernita Pauchay said Thursday.

On Tuesday, three-year-old Kaydance and one-year-old Santana Pauchay died in a field on the Yellow Quill First Nation 260 kilometres east of Saskatoon.

Temperatures were well into the -30s, and felt closer to the -50s C with the wind chill, the night the girls' father, Christopher Pauchay, ventured outside with his two daughters.

Pauchay, 25, was hospitalized with frost bite and hypothermia.

Bernita Pauchay told CBC Thursday her brother is devastated as memories of what happened that night come flooding back.

"He realized what he's done," she said. "He realized he screwed up big time, and that guilt and that blame is always going to be there because when he looks at his scars, that's when he is going to remember it."

According to Pauchay's sister, on Monday night, the father was worried about his younger daughter and had concerns she might have been sick. Pauchay may have been trying to reach help when he became lost in the icy field, she said.

"It scared him a lot to make him run out of the house like that to take the girls like that," she said.

Pauchay told his sister that at some point he dropped the kids, she said.

Her brother was drinking heavily that day, she said, adding that when he's drinking, he becomes a different person.

Community facing problems

Chief Robert Whitehead said the community is struggling to deal with social problems — including poverty, alcoholism and poor housing — and that those issues may have played a role in this tragedy.

The tragic freezing deaths might reignite a debate over whether or not the First Nation should become a dry community, he said.

However, leaders like Phil Fontaine, chief of the Assembly of First Nations, reject that idea.

"The answer is not to turn First Nations communities into dry reserves but to ensure that our communities have the support they need so that they can provide the kind of services and programs that our people deserve," Fontaine said Thursday.