You are sometimes lucky with will & testament entries as very few left them. I couldn't easily see one for father James.
Not sure about the estrangement for son James from parents

He shows as the only child still living with mother in 1891:
Janet Campbell 58, baker b. Bridgeton, Lanarkshire
James Campbell 25, clerk b. Uddingston
Grace Wilson 55, sister b. Rutherglen, Lanarkshire
Address: Old Mill Rd Campbells Rd, Bothwell
Had father William died by now?
Monica