Just posting this until you confirm the actual image of 1808 Bapt has William and not Alex'r Innes as a witness.
1851 Census
Bridge End navie, Inveravon
Alexr Innes 77 Out Pensioner** Of Chalrey Hospille
Elisabath Innes 58 Pensioners wife
William Innes 31 Son Grocer
Janet Innes 28 Daug
Alexr Innes 26 Son
Margaret Stuart 56 Relation
Elspat Hepburn 16 Visitor
Margaret Grant 19 Servant
William Innes 1 Nephew
1861 we have;
Elizabeth Innes 70
William Innes 41
Janet Innes 39
Margaret Stuart 69 Sister*
William Innes 11 Grandson
Janet Innes 2
Trish

3 Nov 1818 Marriage on FreeREG, Alexr INNES/Elizabeth STEWART