The Davies brothers' chemistry is more like gasoline and fire. Ray Davies depicts this relationship in the duet "Hatred" from their final album: https://youtu.be/vCyg45TJEHY

A number of country / bluegrass brothers (many of them known for their vocal harmonies, esp. The Louvin Brothers--what you perceptively call "vocal layering"):

The Dixon Brothers

The Blue Sky Boys

The Callahan Brothers

Jim and Jesse

The Everly Brothers

The Louvin Brothers

The Monroe Brothers

Mainer's Mountaineers

The Delmore Brothers

The Osborne Brothers (2 groups)