So, this is bluegrass: Families concerned about how their kids are growing up, and wanting some wholesome activity to take the kids' minds off the toys and media made by companies that have a vested interest in kids growing older younger.

Consequently, you'll see a lot of family bands in bluegrass music. A lot of them are pretty bad, but a few rise to the top of the heap. Cheyenne and Maddie Dalton, collectively billed as That Dalton Gang, sound as though they might be poised to join the good ones in a few years' time.
 
Here they are with a tune from Bob Wills, and it's even age-appropriate. This one's called "Roly Poly".