This week marked a terrible anniversary for Maple Ridge’s Sandra Gagnon.

It was 20 years ago on Sunday that police raided the Port Coquitlam farm of Robert “Willie” Pickton, and for the first time she began learning about the serial killer who is believed responsible for her sister’s disappearance.

Monday was also a tragic anniversary – the day when her son, who was 23, took his own life.

Her sister Janet Henry, who lived in Vancouver’s Downtown Eastside neighbourhood and had reportedly worked in the sex trade, had been missing since June of 1997.

“We were going to go out that week, but she didn’t call me,” she recalled.

Gagnon got no return phone calls, which was very unusual. As she started asking questions, Gagnon knew something was wrong. Henry, 34, had left her place, leaving all her possessions, and nobody saw her return. Her bank account still had money in it. Nobody could say what had happened to her.

“The not knowing was really ugly,” said Gagnon.

Pickton’s farm became the focus of a large-scale police investigation in February of 2002. Ultimately, the case would result in 22 charges of murder against Pickton. He was convicted in 2007 on six counts of second-degree murder, but is suspected of having many more victims, based on evidence found at the farm.

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It has never been proven that Henry was one of Pickton’s victims, but her face was one of 64 on a poster of missing women from the DTES. A Missing Women’s Task Force believes her disappearance was tied to Pickton.

“We haven’t got any answers, but the task force is almost certain that Janet ended up there. They know more than we do, but they don’t tell us everything,” she said in 2011.

Gagnon testified before a Missing Women Inquiry that investigated the disappearances of 67 B.C. women. She was in regular contact with investigators, pressing them for information, and keeping the memory of her sister alive.

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Gagnon had grown up in Alert Bay until the age of 12, when she moved to Vancouver with her mother and siblings. Little Janet was the youngest of 13 children, four years younger than Gagnon.

Henry also lived in Maple Ridge, working as a hairdresser. Gagnon said her sister she had wanted to quit using drugs and alcohol, and reconnect with her loved ones.

The sisters were close, and on a tough anniversary, it’s not hard for Gagnon to conjure up a memory of better times.

“I just think about how loving she was, and how she was there for me and my kids,” she said. “I remember how she used to come to visit me, and go picnicking down at the Port Haney docks.”

To deal with the loss of her sister, and her son, Gagnon said she would start putting her thoughts and experiences down on paper.

“I try to be strong, but losing a child is the worst thing in the world,” she said.

“I’m going to write a book. Starting today. Hopefully it’s a book that will tell women that they can get through anything.”