Here is the likely descendancy of James Kinnel and John Kinnel, sons of Alexander Kinnel and Christian Forrester. Both called their first sons Alexander.
JAMES KINELL - ELIZABETH FAIR, Marriage: 28 JUL 1775 Aberdour, Fife, Scotland
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ALEXANDER KINELLE - Christening: 07 DEC 1779 Aberdour, Fife, Scotland
JAMES KINNIL - Christening: 04 DEC 1785 Aberdour, Fife, Scotland
DAVID KINNELL - Christening: 17 FEB 1788 Aberdour, Fife, Scotland
(I can only find these children, with quite an age gap though)
James could possibly also be Robert's child. This would have to be checked.
JOHN KINELLE - MARY PATERSON,
CHRISTIAN KINEALL - Christening: 21 JUL 1771 Aberdour, Fife, Scotland
ISABELL KINELL - Birth: 27 JAN 1774, Christening: 30 JAN 1774 Aberdour, Fife, Scotland
ALEXANDER KINELLE - 19 OCT 1778, Christening: 25 OCT 1778 Aberdour, Fife, Scotland
MARGARET KINELLE - Birth: 05 FEB 1781, Christening: 18 FEB 1781 Aberdour, Fife, Scotland
Cannot find John's marriage.