?? Baptism [Scotlands People, Old parish Registers]: LYOL, DAVID; parents JOHN LYOL/JEAN SETON; M; born 22/05/1777; 421/ 10 150; Dairsie [Fife] - a possibility if they named first son for paternal Grandfather & second daughter for maternal grandmother...
However,
https://www.ancestrylibrary.com.au/family-tree/person/tree/74840227/person/44307147278/facts says: David LYALL;
¶born 7 March 1794 in Logie Pert, Angus, Scotland;
¶father Robert LYALL, born 1761, Stow, Midlothian
¶mother not known
¶Half brother Robert LYALL born 8 Aug 1797, Angus, Scotland
¶also a brother William, no dates
Amanda Wem on ancestry.commessage boards: [in 2010] […] I can also send you our family tree! I do know that David`s parents were Robert Lyall and Hellen Straiton - they had 5 children including David but am kind of stuck there!!
Therefore: Baptism [Scotlands People, Old Parish Registers] thus gives: LYALL, DAVID; parents ROBERT LYALL/HELLEN STRATON; M; 10/03/1794; 304/ 10 176; Logie Pert [Angus]
MARRIAGE: Lady Kirk, Sanday Register of Baptisms 1745-1819 [OPR 16/2 - on microfiche at Kirkwall Archives]: Marriage of David LYELL of Start Lighthouse and Barbara THOMSON, Resident of this parish, contracted 11 January and married 29 January. Witnesses Andrew THOMSON and Andrew STRANG. [have download of original]
David LYALL Principal Lightkeeper at Start Point ? - 15 Jan 1825; next principal keeper Charles KING, there from 15 Feb 1845-10 May 1854. Assistants in the interum were ? - 10 Apr 1844 - James JACK; and 10 Apr 1844 - 16 Oct 1860 - Alexander Robert WALLACE
3 Nov 1934: David LYALL, Lady inhabitant: one of many parishoners and inhabitants of Lady to sign a petition complaining about minister Rev Walter TRAILL.
Of Start Point when wife buried 1837
1 Apr 1839: David LYALL, Start-point - male head of family [source: Lady Kirk Session Minutes, Orkney Archives ORC/15/3; per transcription <LKS_Ms misc.xls> on computer at Sanday Heritage Centre]
12 Dec 1839: Mr LYALL, proposed by Session to take square seat at pulpit (between 4th and 5th seat from west door) [<LKS_PH pew holders.xls> Sanday Heritage Centre computer]
Wills & Testaments index: Lyall, David; 20/11/1850; lighthouse keeper, Island of Sanday, thereafter at Millbank Cottage near Peterhead; Extract Testamentary Writing; Aberdeen Sheriff Court Wills, SC1/37/27.
AND: Lyall, David; 20/11/1850; Lighthouse keeper at Start Point of Island of Sanday, thereafter at Millbank Cottage near Peterhead; T. 20/11/1850 SC1/37/27/p1685; Aberdeen Sheriff Court Inventories; SC1/36/27
Mimes MANSON said [pers.com. 2018] David was born abt 1776 - this would make him 20 yrs older than his wife - did he have a first marriage before coming to Sanday as light keeper??
If that is true - could David the Lightkeeper be related to 'my' 4-greats-grandmother Margaret LYALL (before 1770-before 1841) who married Pater MILLER and they had at least 8 children on Sanday between 1789-1805.