Mr McElrea recommended parents follow Ministry of Health advice by making sure cots had no gaps between the frame and mattress that could trap or wedge a baby.
"The infant was in an unsafe sleeping environment due to the looseness of the assembly of the cot," he concluded. "This has directly resulted in the infant's death."
Liiana's aunt Krystle McIntosh said the coroner's findings had come as a complete surprise. "It's terrible ... You feel like you're just getting through it and then - boom. I'm very angry, but I can't do much about it."
The cot was second-hand, and no one had thought about the danger it posed, Ms McIntosh said.
"I personally think that cots should be made illegal. I guess it has to happen to you to think things like that, but keep an eye out."
Parents needed to watch out for seemingly harmless things, she said.
Sudden Infant Death Syndrome NZ chief executive Margret Free said deaths from badly constructed cots were rare.