Hi Stuart,
It's late and I'm tired and confused but thought I'd just through this out anyway.
You say that Elizabeth married Alexander 1815 and that their third son was born 1835, and the fourth, your grandfather, John was married 1860, which would give him an estimated birth year of around 1840 or so. Question...did Elizabeth and Alexander have a load of daughters born between their marriage in 1815 and their third son in 1835...that's a twenty-year gap!
I didn't come up with any Elizabeth's born in King Edward but did find the following that might fit in somewhere along the line...
1851 Census: Heugh Head
James Ogg....... 28..........Head...Farmer Of 32 Ae Employing 3 Lab...Aboyne, Aberdeenshire
Helen Clark.......11.........servant....house servant
William Clark.......52......servant.... Farm Labourer
George MacKie...... 33...lodger...sawyer
Elizabeth Ogg......... 58....Mother...Farmer's mother ...Aboyne, Aberdeenshire
Isabel Ogg............... 53...Aunt......Aboyne, Aberdeenshire
John Watt.............. 11....Servant...shepherd
...I then pulled up this one since the names Isabella and Elizabeth are interchangeable, but then realized that Alexander would have been born three years after he and Elizabeth got married...
1851 Census: Old Braes
Alexander Ogg 33 ...head...farm labourer...King Edward, Banffshire
Isabella Ogg 33 wife...Forgue, Aberdeenshire
William Ogg 11....scholar...Forgue, Aberdeenshire
Alexander Ogg 9 .....scholar...Forgue, Aberdeenshire
James Ogg 7 ...scholar...Keith, Banffshire
John Ogg 4 ...scholar...Keith, Banffshire
...well, I did say I was tired.
Welcome to TalkingScot
Regards,
Anne H