Sophia Sprigg was born in 1766, the daughter of Richard Sprigg and Margaret Caile Sprigg (dau. of John and Rebecca Ennall Caile of England). She was married on February 3, 1785 to Governor John Francis Mercer ; Sophia was the First Lady of Maryland, 1801-1803. She passed away September 25, 1812. 
A portrait of Sophia (Sprigg) Mercer may be found at https://s3-us-west-2.amazonaws.com/find-a-grave-prod/photos/2011/320/23583065_132153437048.jpg
See also: Sophia Sprigg Mercer, MSA SC 3520-2238 -- Sources for an extended bibliography by the Maryland State Archives.
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