About 200 people have attended a candlelight vigil in Hobart's CBD to remember the 24-year-old mother killed in Friday morning's horrific car crash.

Her baby — delivered prematurely after the crash — remains in intensive care but is now in a "stable" condition, while donations for the family have passed $100,000.

Family, friends and supporters laid flowers and lit candles during an emotional vigil at the scene of the crash.

Many supporters said they hoped to let the affected family know they were not alone, while about a dozen Buddhist monks held a silent prayer for the victim.

"We believe that from the tragedy ... we can also learn the lesson about how we can all care about those who have passed away in tragic events," one said.

A family friend said she was buoyed by the public support for the family.

"It just shows the support that this Tasmanian community has got in times of need," she said.

The woman was 32 weeks pregnant and driving home at 1:00am on Friday after dropping off her partner at work.

Police allege a stolen four-wheel-drive ran a red light in Hobart's central business district before ploughing into the woman's car.

She died at the scene but the baby was later delivered at the Royal Hobart Hospital.

Donations and messages of support from across the country

On Friday night, the bakery where the mother's partner works set up a donations page, which has so far raised more than $100,000.

Bakery spokeswoman Karen Ahern said distraught staff had been overwhelmed by the generosity.

She said support had come from locals and interstate, particularly from other bakeries.

"We've had messages from people in Western Australia, Queensland, Melbourne, Sydney — totally heartfelt," she said.

"We've just been blown away by the support we've received from the community for the family. It's just amazing — it's just gone crazy."

About 200 people attended the vigil for the car crash victim. ( ABC News: Bianca Gurra )

Ms Ahern said the man's colleagues were deeply shocked.

"Banjo's [Bakery] is a tight-knit family," she said.

"We just want to do anything we can for a very young family, who've had the most unfortunate thing happen.

"We want to do anything we can to help them make a difference for their future."

The woman's two-year-old son was also in the car and was admitted to hospital with minor injuries.

A 15-year-old boy, who was allegedly driving the 4WD, has been charged with manslaughter.

Police said it was likely two other 15-year-olds and a 12-year-old girl allegedly riding in the stolen car would be charged with motor vehicle stealing.

Police alleged the vehicle had been seen twice before the crash, driving erratically at speeds up to 120 kilometres an hour, but said that, in accordance with policy, they had not pursued the car.