Growing up in the west end of Toronto, he attended the University of St. Michael's College and then began teaching at St. John the Evangelist Elementary School in Toronto. After much discernment, he entered the Paulist Fathers order in New Jersey and went to study at St. Paul's University in Washington.

But everything didn't go according to plan. He was asked to leave as the order felt he worked too hard and was too intense.

He regrouped, entered St. Augustine's Seminary and was ordained at the age of 36. It was at this point Fr. McKillop discovered his passion for youth ministry.

Assigned to St. Mark's parish, after a year of working with teens and young adults, he became director of the Catholic Youth Organization (CYO). Convinced the CYO should include a more apostolic component, he formed Youth Corps in 1966.

First based in parishes around the archdiocese of Toronto, the original Youth Corps team was made up of three men and three women who worked together and focused on a common purpose through community outreach in such activities as The Good Shepherd Refuge. Youth Corps then began holding events with headliners such as Mother Teresa, Henri Nouwen, Dorothy Day and Jean Vanier.

It's founding vision was based on the communal vision of Jesus in chapter 9 and 10 of the Gospel of Luke: "Then Jesus called the 12 together… and He sent them out to proclaim the kingdom of God… After this the Lord appointed 70 others and sent them on ahead of Him in pairs to every town and place where He Himself intended to go."

After 18 years with Youth Corps, he went on to become pastor at Holy Name parish in Toronto and then pastor of St. John Chrystostom parish in Newmarket.

In 2005, Fr. McKillop received the Order of Canada for his work in promoting responsibility and social engagement among Canada's youth.

The funeral Mass for Fr. McKillop was held Feb. 21 and he was interred at Holy Cross Cemetery in Thornhill, Ont.