When I have visited someone during the shiva week, I notice that they wear a torn shirt. I know that the shirt is usually torn at the funeral home or cemetery prior to burial. I assume that the mourner is wearing that same shirt all week, but, I'm not certain.
If the original shirt became soiled, sweaty or smelly, can the mourner take another shirt, tear that one and wear it during the week of shiva? If so, are there any stipulations for the type of shirt he uses (e.g. has to be woprn; can't be freshly laundered, etc.) Does he need to make a new bracha "Dayan Ha'emet" prior to the new tearing?