Thanks, I was trying to guesstimate if perhaps she was with child which would explain why she married young.
Don
The marriage certainly fits - It was in June 1826, first daughter Christiana born ten months later.
John Campbell who marries Christina Sinclair in South Leith in 1826 gives occupation as joiner.
My John Campbell gives occupation as joiner when his first daughter Christiana is born in April 1827.
But the marriage says Christina's father was Angus, the baptism for a Christian Sinclair in 1810, to Angus Sinclair and Margaret MacKay in Reay, Caithness, means that if she was born in 1810, she'd have been about sixteen at marriage, and about seventeen at first childbirth, as Forfarian points out below.
But on the census entries, she gives her age as:
1851: 45 years old (born circa 1806)
1871: 66 years old (born circa 1805)
Indeed. Christiana was 45 in the 1851 census, suggesting that she was born in 1805/1806. I see that Angus Sinclair and Margaret Mackay had Elizabeth, baptised 1804; Angus, 1805; Catherine, 1807; Christian, 1810, Alexander, 1811; Donald, 1812; Barbara, 1816; James, 1820, Elizabeth, 1823; Aeneasina, 1825; so they seem to have been pretty regular in having their family baptised as they came along. Therefore I think it is unlikely that your Christiana was the daughter of Angus Sinclair and Margaret Mackay.
But in the (IMO unlikely) event that she was the daughter of this couple, why is there no Angus among her sons and no Margaret among her daughters?
Thanks all!