A tree on Family Search (but no sources given) gives Robert's father as William Devenport
Birth: 1838 Dublin, Ireland
Death: 1881Warwickshire, England, United Kingdom
(ie he died 10 years before Robert's marriage to Kate Sylvester)
The corresponding GRO death record is
DEVENPORT, WILLIAM HARRIS 42
GRO Reference: 1881 J Quarter in BIRMINGHAM Volume 06D Page 95
But no sources given on Family Search
Hence my original question about Harris as a middle name, does it signify something ?