A mother who lost her three young children and her father in a car crash north of Toronto involving an alleged drunk driver said Monday she is struggling to plan four funerals while grappling with devastating grief.

"It's like the worst nightmare, as a daughter, as a parent, to have to go through and just know it was caused by someone's stupidity... It just kills me," Jennifer Neville-Lake told Toronto television station CP24.

"Planning one funeral is difficult, never mind when you're planning four funerals and three of them are your children and one of them is your dad."

Daniel Neville-Lake, 9, his brother Harrison, 5, and their two-year-old sister Milly, died after the Sunday afternoon crash in Vaughan, Ont..

Jennifer Neville-Lake said her father often took care of the children because she and her husband both work full time.

Daniel was devoted to dance, having taken ballet for several years, and went to Cubs meetings every week, his mother said. He loved to play strategy games, she said.

Harrison -- nicknamed Harry -- was a bilateral hand amputee and was often sick, Jennifer Neville-Lake said. He also had a developmental delay, she said.

"Harry was just so happy. He loved beauty, loved to dance, loved long flowing hair and dresses and pink and My Little Pony," she said.

Milly, she said, was "feisty" and loved to play outside.

The two youngest siblings died together in hospital, holding hands, as their grandmother -- who was driving the van and suffered serious injuries -- sang to them over the phone, Neville-Lake said.

"She didn't know that my dad had died," she said. "She was driving and was pinned in the car and was screaming the kids' names and she couldn't...there was no answer.

"At first she thought it was her hearing but it wasn't until I called her from Sick Kids and I said, 'Mommy the babies are dying, I need you to sing to them please,' so she did, she sang to each of them, and then she found out about my dad."

Police said the family was travelling in the same vehicle when their car was struck by another car. Fire officials said they were T-boned by the other car. A third vehicle was also involved in the crash but its two occupants were not injured.

A 29-year-old man was charged with a dozen impaired-driving offences and appeared briefly in court Monday. Marco Muzzo of King Township, Ont., also faces six charges related to the dangerous operation of a motor vehicle.

He is due in court for a bail hearing Friday. Crown attorney Brian McCallion said he will be contesting Muzzo's release.

Muzzo's lawyer Rudi Covre would only say that his client is struggling.

"I'm sure you can appreciate that this is a very tough time for him," he said outside the courthouse after the hearing.

"It's a difficult period in his life right now. We're going to have to get through it."

The two boys were students at St. Joachim Elementary School in Brampton, Ont. -- Daniel was in Grade 4 and Harrison in senior kindergarten, according to the school board.

Grief counsellors are at the Catholic school and Tuesday's mass will be dedicated to the siblings, spokesman Bruce Campbell said. A memory table has also been set up in the foyer for students to share their feelings and recollections, he said.

"It's obviously a shock," he said.

Meanwhile, hundreds of people moved by the tragedy sought to help the family by donating to an online fundraiser in their name. By mid-afternoon Monday, more than $60,000 had been raised through the GoFundMe campaign.

Many expressed their condolences on the site.

"Such a sad story. I taught one of the boys a few years back in daycare and can't imagine this happening to such a wonderful, loving family," one woman wrote.

"I pray that this family can deal with this most horrific event. The loss of your father and all three of your children is absolutely heart-wrenching. My condolences xo," said another.

MADD Canada said there are somewhere between 1,250 and 1,500 deaths related to impaired driving in Canada each year. Andrew Murie, the organization's CEO, said both the federal and provincial governments need to increase penalties for impaired drivers.