US country singer Kenny Rogers, author of well-known hits Lucille and Lady, turns 70 on Thursday.

His duets with Dolly Parton (Islands in the Stream) and with Sheena Easton (We've Got Tonight) belong to the classics of American music, and there's no sign that despite advancing age and white beard that Rogers will hang up his guitar any time soon.

"I really, really love what I'm doing. People survive longer if they love what they're doing. Because you just don't quit," he said in a recent interview.

He's also kept youthful by the twins delivered by his fifth wife Wanda Miller five years ago. Rogers has three other children from previous marriages.

Born August 21, 1938, in Houston, Texas, Rogers was one of eight children in a poor Texas family. At age 13, he taught himself to play guitar, then founded a series of bands starting in high school.

Nearing age 40, he had his first hit, Lucille. Typical of the plaintive cowboy songs of ordinary people that he is known for, the song told of a woman who walks out on her farmer husband, leaving him in the lurch.

"You picked the fine time to leave me, Lucille," the man sings. "Four hungry children and a crop in the field."

Rogers is modest about his success, despite the millions of dollars he earns every year from his art.

"I've never considered myself a great singer, but I am a great storyteller," he said.

That approach gave him the crossover into the pop charts, such as Lady and the duet with Kim Carnes, Don't Fall in Love with a Dreamer.

He has brought out a series of new albums, including Water and Bridges in 2006 and the single, I Can't Unlove You, which hit the US Top 40 recently.