Might be useful -
Using Ancestry Scotland Census 1901, at 10 Alma Street, address for your John MORRISON at 1906, has James MORRISON 28 years and John MORRISON 20 years, both born Ireland, shipyard labourers, boarders in household of Jane HUNTER and children.
I think that 10 Alma Street is a tenement with many people living there.
What names does your John MORRISON give to his children?