Thanks for that.
I have all the info on James Brown and Janet including their Marriage Banns.
Found the Census record you mentioned on Ancestry, Will check out the leads on the children you mentioned.
Have found a public tree which also seems to be the same family.
According to that tree Jane Martin died on 16 Jan 1864 at Old or West Kilpatrick, Dunbarton, Munroe's land, Hardgate, Death, cancer of the stomach, 9 a.m.
That record also states that Christening at Luss, Dunbarton Age 8, 17 Apr 1794 so will need to check those out.
have also done a search on Family search for Walter Angus and found a possible match for his birth / baptism Parents: Robert Angus, Mary Knox, baptism/christening date: 19 Nov 1780, place: CADDER, LANARK, SCOTLAND birth date: 05 Nov 1780.