Not sure if you have this - the 1871 surname is from a source who says it is PAUL and the 1881 is from 2 Sources who say it is says SAUL or SAULS
1871: Borthwick, Midlothian
Ref: Parish 674, ED 1, pg 15
Address: Villiage South Midd Caton
Head: James PAUL 30, Quarry Labourer, b Ireland
Wife: Ann PAUL 28, b Ireland
Dau: Bridget PAUL 4, b Temple Edinburgh
Dau: Catherine PAUL 3, b Borthwick Edinburgh
Son: John PAUL 1, b Borthwick Edinburgh
Lodger: Mary BOGANS 41, Farm Servant, b Ireland
1881: Dalkeith, Midlothian
Ref: Parish 683, ED 14, Pg 19
Address: No. 23 Cowden Cottage
Head: James SAUL 35, Labourer At C Work , b Ireland
Wife: Ann McDONALD, 34, Labourers Wife, b Ireland
Dau: Bridget SAUL 14, Scholar, b Temple Edinburgh
Son: John SAUL 11, b Borthwick Edinburgh
Son: Peter SAUL 7, b Lochgelly, Fife
Son: James SAUL 5, b Cockpen, Edinburgh
Dau: Rosan SAUL 1, b Dalkeith, Edinburgh
Son: Bartie SAUL 29 days, b Dalkeith, Edinburgh
As well as James SIAUL born 1876, mentioned above the IGI has births to parents James SAUL and Ann (I searched Ann's name as McDONALD, but these all came up in result):
Catherine SAUL 21 Sep 1867 Borthwick - mms: McDONNELL
John SAUL 16 Jun 1869 Borthwick - mms: McDONNELL
Ann SAULS 9 Aug 1872 Borthwick - mms: MsDONNELL
Peter SAUL - 2 Jul 1874 Auchterderran, Fife - mms McDONALD
The family is in Cockpen 1891 (James 46, Ann 47) and 1901 (James 58, Ann 57) - let us know if you want the details?
Cheers
AMBLY