Seeking more information on David Greig b. ~1780 in Scotland, mar. Agnes Brown in Straiton Parrish 1802., death: UNKNOWN

13 or so children:
Agnes
David b. 1806 to Canada to Detroit MI m. Catherine Inglis of Glascow?
William to Hawaii to Australia to Fanning Island d. San Francisco
Elizabeth
Marion to Hawaii
James

Need more information on David Sr b. ~1780 and
his wife Agnes Brown. Story has it that they or he was originally from Aberdeen. She died in 1822 in Ayrshire.

Any help appreciated.