Almost 1,000 people attended a funeral in Pickering on Wednesday to pay their respects to a father and his two children killed by an alleged drunk driver.

Roger St-Denis and his son Paul, 21, and daughter Angela, 15, were killed two days before Christmas while travelling along Interstate 99 southeast of Pittsburgh, PA.

St-Denis' wife Angela and another daughter, 22-year-old Therese, survived the horrific crash.

The collision occurred at about 3:40 a.m. Family members were either sleeping or watching a movie at the time.

Local police said a pickup truck heading the wrong way caused the accident.

The St-Denis family was driving from Ontario to Florida where they were going to take a Caribbean cruise.

"Life is fragile, we found that out this week," Father Viateur Laurin said on Wednesday, the Toronto Star reported.

The service was conducted partly in English and in French.

Durham Region Police Chief Vern White was among those in attendance, the Star reported, and many members of the sea cadets were also present. Angela was a sea cadet.

In media interviews after the crash, Angela said she had forgiven the suspected drunk driver. She only asked he never get behind the wheel of a vehicle again.

"We were the perfect family," said Angela, who teaches elementary students in Malvern.

The family was well-known for their tireless work in the community.

A 23-year-old Pennsylvania man, Jeremy Grimes, is facing three counts of vehicular homicide while driving drunk.