The 19-year-old University of Otago student died in a stairwell pile-up four years ago.
Coroner Heather McKenzie’s five-day inquest into Ms Crestani’s death will begin at the Dunedin courthouse on Monday.
"It’s been pretty taxing on us as a family really, having to relive this over and over again for four and a-half years," she said.
Ms McMillan and Sophia’s father Bede Crestani were hoping the inquest could clarify events surrounding their daughter’s death and bring further change around drinking culture.
"We want to know what happened to Sophia in that last hour. We also want to know about the circumstances that led up to that," Mr Crestani said.
"We want to see the authorities take another big step, be courageous and do stuff outside the norm ... and make Dunedin a really outstanding place and limit the extreme behaviour."
Ms McMillan said she hoped the government might make changes following the inquest.
"There are laws in other countries around recklessness and negligence which don’t seem to exist in New Zealand ... that’s something that we would really like to see change. Because why will people stop that behaviour if there’s no consequence?" Ms McMillan said.
Following their daughter’s death, Miss Crestani’s parents advocated for change in the Dunedin drinking culture.
"As outsiders to Dunedin, when we came there, we were horrified at the state of the student flats and the behaviour and what was going on," Ms McMillan said.
She explained locals seemed to accept the behaviour as "normal" but said it "shouldn’t be tolerated".
"Sadly, there is still that element of student culture ... where it’s excessive drinking and excessive behaviour," she said.
"We just want the students to realise that you do that and you risk your life ... and Sophia wasn’t even doing anything risky, that’s the sad thing. She was just at a party enjoying herself."
It incorporated a range of initiatives including informing students about party safety, as well as education about two-storey properties.
Mr McMillan said he hoped to support safe drinking organisations such as Hold on to Your Friends (HOTYF) through the inquest.
HOTYF spokeswoman Louisa Mason said she also wanted the dangerous drinking culture in Dunedin to be recognised through the inquest. The current efforts made by the University of Otago had been "insufficient".
"I recognise that no two students’ experiences are the same - some encounter much more harm than others," Ms Mason said.
"I hope people can open up and start having an honest conversation about what the Dunedin student experience actually is like for too many students."
