Mary Suttie Johnston's age on the 1861 Census shows as 7, that would make her birth in 1854...maybe just before her parents' marriage. I can't find an entry for her birth in 1855.
In respect of Elizabeth Ramsay Dorward, these look like her siblings. To parents John Dorward and Barbara Ramsay:
1. JOHN DORWARD Birth: 03 FEB 1854/ Christening: 09 APR 1854 Guthrie, Angus, Scotland
2. WILLIAM DORWARD Birth: 14 DEC 1855 Guthrie, Angus, Scotland
3. JAMES RAE DORWARD Birth: 30 AUG 1857 Guthrie, Angus, Scotland
4. DAVID DORWARD Birth: 15 JUL 1859 Guthrie, Angus, Scotland
5. ELIZABETH RAMSAY DORWARD Birth: 11 NOV 1861 Guthrie, Angus, Scotland
6. MARY ANN BALLA DORWARD Birth: 28 JAN 1864 Guthrie, Angus, Scotland
7. PETER DORWARD Birth: 08 NOV 1865 Guthrie, Angus, Scotland
8. ROBERT LAING DORWARD Birth: 29 APR 1868 Guthrie, Angus, Scotland
9. CATHERINE LAIRD DORWARD Birth: 29 AUG 1869 Guthrie, Angus, Scotland
10. MARGARET RAMSAY DORWARD Birth: 22 FEB 1871 Guthrie, Angus, Scotland
11. GEORGE DORWARD Birth: 24 MAR 1872 Guthrie, Angus, Scotland