Looking around on Familysearch they had Christened, St Clement Danes, Westminster;
JOHN, Nov 1832
WILLIAM, Dec 1832, Died 27 Nov 1832
CHARLES, 29 Nov 1834
WILLIAM, 30 Aug 1835, Died 28 Oct 1836
SUSAN ELIZABETH, 25 June 1837
The at St Mary Le Strand Westminster;
ELIZABETH JEMIMA, 7 Aug 1846, Birth 6 June 1846
WALTER, 3 May 1850, Birth 20 March 1849
I cant find Theodores Christening on there.
Possible Mariage;
John LYALL to Susannah DANIELL, 13 Aug 1828, St Clement Danes, Westminster ( on Anc.)
As I said a Birth Cert would be needed to confirm this is the right Marriage.