Mary and James married in 1900 in St Mary's Greenock, her father was listed as deceased.
Widow, Ann Jane McPhail, three of Mary's siblings and a Grand-daughter, Ann Jane McGee are in Greenock in 1900. Same Dalrymple Street address as given on Mary's marriage cert.
The children's ages range from 22 - 15 all reportedly born in Greenock.
Can't see this family in or around Greenock in 1881 or 1891 using search strings of M*c*a?l
There is a birth cert for Richard McPhail in Greenock in 1886, this should give the place of the parents marriage.
Ann Jane (McKillop) McPhail died in 1931 in Greenock, that should give her parents
There are no deaths of John M*c*a?l in Renfrewshire between 1885 (a year before son Richard's birth) and 1900 (when Mary marries).
Since John and Ann Jane were married after statutory records were kept in Ireland, the certificate from 1868 will have both father's names. Church records, if extant, may name both sets parents.
Loads of Rathin families lived in Dalrymple Street I'd be VERY interested to hear what you find out about this family.