Laurie -
Iver or Edward
McCallum, as he later appears in some records, is the son of
Archibald and Euphemia
McCallum, nee
McCallum.
The family lived at Auchindrain (now an open air museum) and much can be found regarding the families descendants here. Christian was Iver's 1st wife, and they had at least 6 children - the 5 you list and another James, as the 1st James passed away as an infant.
Christian, who died at Auchindrain in 1842 was the daughter of
Duncan McCallum and Janet (last name unknown). Her sister Mary was married to a Neil
Dewar.
Iver/Edward remarried after Christian's death to
Isabel McLarty and had at least three additional known children. Isabel died in 1886 at Auchindrain and he followed in 1890.
Hope this helps.
J