Bill Sables is also Older than Dirt, and plays with two very talented sprouts, Sam and Ian. They called their album "Bridging the Gap", but I'm not sure if that's intended to be the name of their band or not. Maybe something that refers to the age spread that you have (I mean that the band has! I wasn't referring to your spare tire!!!)

Another possibility is to modify the word "grass" with something new. We've heard about newgrass and dawg-grass--maybe something else that tries that trick.