They would take their time walking past the pine trees and poison oak, talking about school, music, girls, football -- the same topics the best friends had been discussing for years.
Walnut Creek. Renfrow was uneasy about the prospect, and said it didn't sound like a good idea. But Tollefson later told recruiters that he was interested and began wearing olive-drab T-shirts and uploading military photos for his computer screen saver.
After graduating from high school in 2005, Tollefson held various odd jobs and, as friends described it, seemed lost when it came to focusing on a career.
He eventually joined Renfrow in nearby San Ramon, where they shared an apartment and worked at a mortgage loan company. When the company folded, Tollefson moved back north to live with his parents in Concord. A few weeks later, he joined the Army.
Renfrow worried that it was the wrong decision, but said that Tollefson sounded confident and dedicated when he called from Ft. Benning, Ga.
"It was like he was a completely different person; he'd grown up overnight," Renfrow said. "I started thinking it was a good idea. Maybe this is what Ben needed to kind of push him a little bit."
While in boot camp, Tollefson kept in touch with his girlfriend, Natalie Hartley. They had recently broken up, but one day Hartley called with exciting news: She was pregnant. The two reconnected and were married Dec. 6, 2007. Their son, Mac, was born four months later.
Tollefson was assigned to the Special Troops Battalion, 2nd Heavy Brigade Combat Team, 1st Infantry Division at Ft. Riley, Kan., where his new family lived with him for a few months. Then, last September, Tollefson deployed to Iraq for what was supposed to be a 12-month tour.
But on New Year's Eve, Charles and Mary Tollefson received a visit from military officials bearing heartbreaking news: Their youngest son, Pvt. Benjamin Bryan Tollefson, had died that day in Balad, Iraq, of injuries suffered in a mortar attack on his unit in northwest Baghdad's Ghazaliya neighborhood. He was 22. In addition to his parents, wife and son, he is survived by a sister, Jaime, 29; and a brother, Jeffrey, 25.
A funeral service with full military honors was held Jan. 10 at Walnut Creek Presbyterian Church, which filled with more than 1,300 people.
Friends and family members spoke about the goofy guy with the high-pitched laugh who did hilarious impressions of hapless surfer dudes, who knew how to scam his way out of homework and soccer practice, whose eclectic musical tastes ranged from electronica to heavy metal to rap to pop, and who joined the Army as an out-of-shape, aimless wanderer and quickly morphed into a burly, motivated man.
The service was an amazing tribute, Mary Tollefson said, one she hopes her 1-year-old grandson, Mac, will someday understand.
"More than anything, Ben wanted to provide for his family, and he knew the military would be able to do that," she said. "I've never seen a person love their kid as much as he loved Mac. And that is what I want Mac to know, how much his dad loved him."
For Renfrow, 22, there's never been any doubt about how much his friend cared for him. Since meeting in junior high, the two were known for their shared rituals -- like meeting at Jack in the Box late at night and hanging out in the car until the wee hours, or never forgetting to jokingly exchange garish wedding picture frames with photos on Valentine's Day.
Every Memorial Day weekend, the friends made sure to go camping at Napa County's Lake Berryessa. And, of course, there was their annual trip up Mt. Diablo.
This year, as the end of January neared, friends offered to join Renfrow on the trail. He turned them down. Then, one crisp morning, he set out for the mountain with a new tattoo on his forearm -- the initials B.B.T. -- and began the hike alone. It was tradition.