I have been researching this side of the family as well.
Records so far suggest that James Blackie married Helen (Janet) Hutton / Houston in about 1807 in Channelkirk, Scotland.
This parentage gives: Jean Blackie (b) 18/10/1808; John Blackie (b) 9/2/1811; Ann Blackie (b) 18/9/1812; Elizabeth "Betty"Blackie (b) 22/5/1815.
John apparently married Margaret Heatly on 23/5/1836.
Would you be able to verify your info please just in case I am on the wrong track.
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