Jagit Grewal shows her two-year-old grandson Devin Grewal where her husband, Daljit Singh Grewal, and his grandfather's name is on a monument honouring those who died, during a memorial marking the 25th anniversary of the Air India bombing in Vancouver on June 23, 2010. (Darryl Dyck/Canadian Press)

Families of the victims of the 1985 Air India bombing are expected to gather at the memorial site in Vancouver's Stanley Park on Saturday evening.

Every year, family members hold a special ceremony to remember loved ones who died when a bomb aboard the plane exploded over the coast of Ireland, killing 329 people.

Only one man has ever been convicted for his role in the tragedy which has widely been believed to be the work of Sikh extremists.

"Some of these people have forgiven the bombers and some of them have found a purpose in their lives," said journalist Gurpreet Singh. "They're trying to help others by running free schools and hospitals for people in India."

Singh recently wrote a book highlighting how some families have channelled their grief into charity work abroad and in Canada.

"Some people are doing the same thing by living in Canada like sending sponsorships to baby children, whether in Ireland or anywhere in India," he said.

"Either way, it's very difficult for those people to do it. They're trying to overcome the hatred and anger, and ... [it's] a kind of pursuit for a positive energy, so something that's very inspiring."

The memorial is slated to begin at 6:30 p.m. PT at the Air India Memorial in Ceperley Playground in Stanley Park.