I'd wondered whether the 12 year old Mary in the Ballacottier, Andreas household of John Sayle and Ann nee Cowle in 1841 could be from a first marriage. The only sticking point I can see is the fact that John and Catherine had a son, Robert, in 1832 who doesn't appear in the burial index as a small child --- and then there's a Robert whose baptism I can't find in the IGI, but who was age 4 in 1841, and age 23 in 1861.

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1841
Andreas, district 1, image 1
Ballacottier
John Sayle 40 mason
Ann 30
Mary 12
Eliza 6
Robt 4
Chas 2
Catherine 2 months

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1851
Bride 1/7
John Sayle head mar 55 stone mason
Ann wife 44
Charles son 13
Catherine dau 11
James son 9
Thomas son 7
Daniel son 3
all b Bride

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1861
Bride 2/16
John Sayle head mar 65 ag lab
Ann wife 52
Robert son mar 23 mason
Charles son unm 21 mason
Daniel son 12
Philip son 10
John Kewley illegt son 6
all b Bride

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Do you think that this Robert is the one born to John Sayle and Cath Ratcliffe, and that the enumerators got his age wrong in 41+61 ?

Do you know what became of Robert b 1832 ? And what about Mary Ann and the other siblings ?

Jean C