The baby was head down in a crate of the fermented potato-yeast concoction, her legs sticking up in the air.
Details about the 10-month-old's death last spring near Fox Lake emerged publicly for the first time in court this week.
A document obtained by The Canadian Press says the baby's 12-year-old brother made the discovery May 29 when he came home from school.
Their mother, Viola Ribbonleg, entered a guilty plea Tuesday to a charge of criminal negligence causing death for failing to provide adequate child care. The 32-year-old woman is to be sentenced in Fort Vermilion court July 15.
Court heard that Ribbonleg's son saw her and another man drinking brew in the trailer on the night of May 28. The next morning, Ribbonleg was drinking again and her son believed she was drunk. She asked her son to come home at lunch and babysit for the afternoon.
When he returned with two friends, the door was locked, so one of them climbed in through a window.
The boy's mother was sleeping on the floor. Two men were asleep on one of the couches in the living room.
The boy pulled the baby out of the brew, which was in the crate beside a couch, and then woke up his mother.
The document says Ribbonleg got upset, tried to wake the infant and told her, "I love you." Clutching her child's limp body, the woman ran to a nursing station.
As paramedics tried to revive the baby, the mother knelt on the floor, crying. When they declared Lexi dead, Ribbonleg begged staff to do more to save her and hit one of the paramedics on the chest.
She picked up the child and refused to put her down, repeating "dead baby, dead baby" and some words in Cree.
She also tried to breast feed the dead child.
The court document, called an agreed statement of facts, says a nurse noticed Ribbonleg was slurring her words and smelled strongly of homebrew — and that the same smell was coming from the baby's body.
Ribbonleg denied drinking, but the document says the nurse, Sara Peters, believed the woman was intoxicated and "shouldn't have been doing any activities that require attention."
The document says Peters told investigators Ribbonleg refused to let go of Lexi for about three hours, even as the little body turned cold and blue.
The document says the baby's diaper was dry, but her fingers were wrinkled from being immersed in the alcohol.
The document quotes the nurse as saying Ribbonleg insisted she had been "watching the baby the whole time."
Ribbonleg "kept looking in Lexi's mouth and saying that Lexi must have choked on something ... She said she and some other men had been outside the house when this happened to Lexi."
Medical staff had alerted tribal police and Mounties later joined the investigation.
Fox Lake, a community of about 2,000 along the Slave River, is part of the Little Red River Cree Nation.
The document says an autopsy confirmed the child drowned.
Toxicology tests also showed the homebrew contained about eight per cent ethyl alcohol, slightly higher than in beer.
The person who made the brew told police it was a mix of water, rolled oats, sugar, potatoes and yeast. It had been left to ferment for about a week in a plastic bag inside the crate, typically used to hold milk cartons.
Ribbonleg's lawyer, Michael Nanooch, refused to comment.
— By Chris Purdy in Edmonton
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