Trout Fishing in America.

Sometimes, songs just show up on the doorstep of the duo Trout Fishing in America.

Or, more specifically, they show up in the bathroom.

Take, for instance, one morning as member Ezra Idlet worked to get his young son ready for school.

“He looked in the mirror and said, ‘Hey, dad – look. My hair had a party last night,'” Idlet recalls. “And I just freaked out. I thought it was hysterical. And as soon as he got on the bus to go to school, I called Keith and said, man, I don’t know how it goes, but this is the name of our next song.”

“Keith” is Idlet’s musical partner for more than 30 years, Keith Grimwood.

The duo, which is known for its children’s songs that also appeal to adults, comes to Lawrence Friday for the Lied Center’s annual Family Concert. The free show starts at 7 p.m. outside the center, and is preceded by the Family Arts Festival.

Trout Fishing in America, which got its name from a novel by Richard Brautigan, most recently performed at the Lied Center in 2004. The band has received numerous honors, including three Grammy nominations. Its latest nomination was for “My Best Day,” a live album that also spawned a DVD.

“We try to write about things that real people have experience with,” Grimwood says. “And we try to write on several different levels at the same time, ala ‘Rocky and Bullwinkle,’ something like that.”

They also write with children at workshops. That’s how songs such as “Alien in My Nose” and “My Pants Fell Down” were born.

The duo – Grimwood on bass, Idlet on guitar – will be joined by their producer, multi-instrumentalist Fred Bogert, onstage Friday night.

“It’s a really entertaining show,” Idlet says. “Generally you end up leaving the show feeling better than when you got there.”

Trout Fishing in America also will be the subject of Friday’s Pulse Podcast, which can be found at www.ljworld.com.