My apologies, as Alexander & Isabella were the only Barr family in Ochiltree in 1901
I made a wrong assumption.
Below were on the 1911 census at Ochiltree
The cert for Isabella states she was the widow of Hamilton Barr, Coal Miner parents Joseph Thorburn and Janet. They were married Paisley in 1885, some children born there but their youngest child was born Ochiltree in 1904
As this was the only Alexander on the 1911 census, I thought he was the husband of Isabella Martin but at a different reference number, not 609/6/17.
ALEXANDER BARR 1911 50 609/ 6/ 16 Ochiltree Ayr. No other Barr's at that reference.
As regards this Alexander Barr, ploughman, married to Isabella Patterson Marshall parents Alexander Barr and unknown mother. I cannot trace him or his marriage in Scotland or Ireland?
Whilst checking the records I came across this death. Daughter of Alexander & Isabella?
ISABELLA MARTIN BARR, age 101 mmn MARTIN
1991 682 / 50 Old Cumnock.
Colin