I'm excited for you!
I think I have found niece Fanny living at her grandparents James and Mary in Annan:
James Carlyle 58, Retired Cotton Skinner, b. Annan
Mary Carlyle 55, b. England
Joseph Carlyle 18, son, b. Annan
David Carlyle 17, son, b. Annan
Mary Anne Carlyle 15, son, b. Annan
Faney Carlyle 6, granddaughter, b. England
Address: Lady Street, Annan, Dumfrieshire
This looks like Fanny's birth details:
Births Jun 1854 CARLYLE Fanny Carlisle 10b 378
James and Mary seem to have had lots of children. These are just some of them on IGI. Only the girls are showing - looks to be one of those films where LDS only loaded on the girls:
1. JANET CARLYLE Christening: 08 AUG 1830 Annan, Dumfries, Scotland
2. FRANCES CARLYLE Christening: 04 MAR 1832 Annan, Dumfries, Scotland
3. JANE CARLYLE Christening: 17 AUG 1828 Annan, Dumfries, Scotland
4. JANE CARLYLE Christening: 01 DEC 1833 Annan, Dumfries, Scotland
5. MARGARET CARLYLE Christening: 01 OCT 1826 Annan, Dumfries, Scotland
This looks to be the OPR entry for parents' marriage:
JAMES CARLILE Marriages: Spouse: MARY BARNES
Marriage: 23 MAY 1824 Annan, Dumfries, Scotland
Thomas would look to be a post 3 month honeymoon baby
I haven't found the family as yet in the 1841 Census but I can see them in Annan in the 1851 Census. I'll post tomorrow as I am getting tired and I'll start to make mistakes
Niece Fanny may prove to be the key to your Thomas
Regards.
Monica