I sometimes listen to Larkin Poe. They're 28 and 29. They've gone through many stages and have played for years. They started out as a bluegrass band with their older sister who quit to get married, etc.
I've known about them for two years or so. But I looked up some older videos. In their early days, they were transitioning. But they had a bassist that reminded me of Berry Oakley. Back then they were just playing small gigs mostly wherever they could find them. I think they were naturally developing their own style. I think I would have liked being at one of those earlier gigs if I could have had a choice of gigs to go to. Here are some songs from their latest album which was nominated for a Grammy, but lost out to Gary Clark Jr.