Rohan Marley is saving small farmers while his brother Ziggy is saving the food system from the taint of GMOs.

Bob Marley's music may conjure up images of palm trees and sandy beaches, but the musician, who would have turned 67 years old today, was a real humanitarian and social activist whose songs spoke more of equality and dignity for the world's downtrodden than of happy-go-lucky island life.

During his short lifetime, he earned the Peace Medal of the Third World from the United Nations for his efforts at ending racial segregation in Jamaica and in Africa, he performed twice in an effort to subdue political tensions in Jamaica, and he was commonly known to give cash away by the thousands to mothers who couldn't afford to send their kids to school.

In the 30-plus years since his death, his family has found new ways to get those same messages across, trying to fix modern-day problems of food inequality and exploitation of the poor. In honor of Bob Marley's birthday, here are three ways his kids are keeping his social activism alive:

Helping Small Farmers
Bob Marley was born on a farm and said a number of times that he wanted to return to farming one day. But it's his son Rohan Marley who's making that a reality, establishing an organic coffee farm in Jamaica that's meant to revive not just the country's depleted soil health, but also the economic situation of poor rural farmers. Most of the 90,000 coffee farmers in Jamaica earn just $1,660 per year; meanwhile, the country's coveted Jamaica Blue Mountain coffee beans, some of the highest-quality beans in the world, can fetch up to $50 per pound.

In addition to Marley Coffee, Rohan founded a line of headphones and electronics accessories in January 2012. House of Marley sells headphones and speaker systems made from Forest Stewardship Council–certified hardwoods.

Standing Up to Big Ag
A music superstar in his own right, Ziggy Marley lent his support and his music to a public-service advertisement for Just Label It, a national campaign trying to get the U.S. Food and Drug Administration to require food companies to label GMOs, ingredients that have been genetically altered so they'll withstand higher doses of pesticides.

And he's taken his opposition to GMOs to store shelves with Ziggy Marley Organics, his line of certified-organic, non-GMO coconut oils and hemp seeds. And who does he say influenced this greater awareness about the problems with his food system? His parents. "We didn't go to the supermarket growing up," he told TheRoot.com. "I don't remember seeing supermarkets at all until I was a teenager. We had the garden, we had the ocean, and we had the farms. Everything was fresh and everything was organic."

Bringing Dignity to the Underserved
"One Love" was one of Bob's most famous songs, and now it's the message his family is trying to spread around the world. The 1Love Foundation, run by Rita (Bob's wife) and 11 of his children, raises funds for and awareness of global issues devoted to children's health and education, environmental sustainability and peace. They've raised $100,000 for charity:water, a group that used the money to bring drinking water to 4,000 children in Ethiopia. They've raised money to supply orphanages in Kingston, Jamaica, with formula and other necessities, and they're continuing Bob's musical legacy by supporting programs that bring music education into some of the poorest schools in the U.S.