‘I need to know’: Family of teen who vanished nearly a half-century ago plans new search for answers

(Update: Adding video, comments from family members)

BEND, Ore. (KTVZ) -- On the 47th anniversary of her second cousin going missing, Deni Grove and a group of 11 people will reignite the search for him.

Grove learned about the disappearance of her cousin, Rodney Lynn Grissom, during the pandemic and has been investigating ever since.

"We're trying to put an end to it, close that chapter and see what we can do," Deni Grove said Tuesday.

Grissom, a 14-year-old from Cornelius, and his girlfriend, Karen Lee, went missing two days apart in May of 1977. Years later, investigators found items belonging to the two near Soda Fork Road, east of Sweet Home near the South Fork of the Santiam River.

"It's still really hard, after all these years," Grove said. "So we're going into this search with cautious optimism. The chances of us finding anything, are very, very slim to none."

The pair vanished at a time in 1977 when notorious serial killer John Ackroyd was prowling Highway 20 for victims, as The Oregonian/OregonLive chronicled in this special report, "Ghosts of Highway 20." Grissom went missing on May 24, 1977 and Lee two days later.

"He (Ackroyd) had a distinct, style of abducting and disposing of the bodies," Grove said. "So after viewing the items that were found, they concluded that Rodney and Karen were both victims of John Ackroyd."

It's been seven years since the area was last searched. Grove hopes she can bring closure to herself and her family, "because I need to know. I need to know," she said.

Grove has partnered with Ryan Auclair, who has been searching the area for a year. He keeps track of his searches through his blog.