A turbine assembly includes a first turbine blade circumferentially adjacent to a second turbine blade. The first turbine blade includes a first platform with a first underplatform surface. The second turbine blade includes a second platform with a second underplatform surface. The first underplatform surface and the second underplatform surface at least partially defines a cavity. A damper with a platform rub surface is included adjacent the first underplatform surface and the second underplatform surface. A seal is included with a forward portion, an aft portion, and a damper interface portion therebetween. The damper interface portion extends along a damper underside and the forward portion and the aft portion adjacent the first underplatform surface and the second underplatform surface.