Is it John McCallum b. 1886, apprentice brassmoulder, living at 49 Dumbarton Road, Govan on 1901 census with siblings and parents Adam McCallum and Catherine McLean?
Check deaths on Scotland's People first if I were you ... there are records for two chaps named John McCallum born +/- 1 year of 1886 in Govan ... so worth investigating who they were if only to rule them out