Devaney met his wife in college in the '80s; her family had been going to the festival for years, so she took him along. He had no idea what he was getting himself into.
"It's August. It's miserably hot. We have a little camping stove, this tiny little tent," Devaney recalls. "We show up on Friday, and the place is just a mob scene. There's no place to camp."
But the experience of camping out, seeing concerts during the day and then participating in nighttime campfire jams, kept Devaney going back. Now, 23 consecutive years of attendance, three children, and hundreds of hours of music later, he's become part of a community. Every August, members of Devaney's network of Folk Festival family and friends stake out a campsite, setting up a large common tent and individual family tents around it. A kitchen and seating area are set up; meals are planned in the weeks beforehand to accommodate the dozens of campers in their group.
When the Devaneys, who live in Baltimore, began to have children, they wondered, briefly, whether to continue the annual trip to the Schwenksville festival ground.
"You start to think to yourself, are you really going to do this?" Devaney said. "She had my daughter [Clair] in June  and a month and a half later is the festival. But we're like, 'Wait a minute, we can't break the streak . . . we can't not go to the festival.' "
In the case of youngest son Logan, 10, Devaney's wife, Katherine, attended the festival even though she was "fully pregnant" before giving birth in October, he said. Questioning stares and bewildered looks were common in those years, Devaney said, but he wouldn't change a thing - his kids are now fully entrenched.
Their daughter Clair, 16, plans to continue attending the festival as long as she can.
"There was a phase definitely from 12 to 14 when I was kind of over it, because I was starting to do the whole pop-music thing," Clair said. Still, she never stopped going. "We have the bond of each campsite, and the ritual of it is cool. It's one of our most important family traditions."
Rob Bralow, chairman of the merchandise committee, understands the appeal for kids; he's now 29 and this year will be his 30th festival, thanks to his in utero attendance in 1982.
"As a child, it became a bigger family," he said. "You go to the Folk Festival and it's not just your parents with you, it's hundreds of other families that all look out for the kids, it's really a great time. . . . "
Bralow, who remembers playing tag backstage for hours into the night, said his "family" became even bigger when he began volunteering around age 14. Fifteen years later, that family is taking on new meaning.
Bralow got married in April; his wife, a doctor at New York Presbyterian Hospital, wasn't able to schedule the time off to attend the festival until this year.
"She plays the flute and knows how to play piano, and we love going to New York City Philharmonic, so she has her opinions of music," Bralow said. But the real nervousness isn't about the music: "It's probably most nervous to me because it's like introducing her to my family all over again."
Both Devaney and Bralow said that their experience is not unusual, with multiple campground communities spanning family generations and long distances. Bralow, like Devaney's sister-in-law's family, lives in New York City. Bralow's campsite sometimes includes festivalgoers from Chicago; Devaney's has had a brother-in-law from San Diego.
The music is the draw, festivalgoers say, but it's not always about the big acts or the formal concert performances.
"I don't know which part I like better, going to the concerts or just hanging out at the campsites," said Devaney's sister-in-law Susan Bockenhauer, 49.
As the acts at the festival have changed, she said, she's always been able to find something she likes.
And that may be the Folk Festival's biggest success: offering music and activities to suit all tastes. Bralow enjoys traditional folk and classic rock, but loves live music in all forms, including modern acts that stretch the boundaries of "folk." He's looking forward to seeing Trombone Shorty. Devaney shares similar tastes, anticipating John Hiatt and Lucinda Williams. His kids say they don't scout the performances beforehand, but generally have their ear to the modern stuff: Mumford & Sons, the Avett Brothers.
"Since our family's been going there for a long time, it's kind of a must-go for everyone, even if it's going to be rainy and mud piles everywhere, you still have to go. Usually it's still fun because you enjoy the music," said Devaney's son Aiden, 14.
There are other benefits - "They don't make us brush our teeth!" - and not all the music has to appeal to everyone, he said.
"If we don't think it's gonna be good, then we don't go to see the music," Aiden said. "Then we just stay at the campsite."
If You Go
51st Annual Philadelphia Folk Festival
Friday through Sunday, Old Pool Farm in Upper Salford Township, near Schwenksville
Tickets: $65-$89 daily, $145 three-day pass. Discounts for youth under 17; additional fees for camping and reserved seating options.
Information: 800-556-3655, www.folkfest.org
Contact staff writer Jonathan Lai at 215-854-5151or firstname.lastname@example.org, or follow on Twitter @elaijuh.