Gertrude died in 1951 in Warren, and no trace of Emil in "Pennsylvania, Death Certificates, 1906-1964"
A widower in his late 80's, he could have been living with or near one of his children.
Not in PA then, but the closest place is Ohio.
It's a long shot, but if he was Stephen Emil AND 1958 burial is wrong, you could look at this one:
Ohio, Deaths, 1908-1932, 1938-2007
Stephen E Johnson
Birth Date: 1871
Residence Place: Medina, Medina, Ohio
Death Date: 6 Jul 1958
Hospital of Death: Long-Term Care Facilities
Death Place: Clark, Ohio
Age at Death: 87
Marital Status: Widowed