Genealogics shows her as a daughter of William Crawford of Auchinames and his wife Anna Lamont, citing Gary Boyd Roberts, RD600 (2004).
Footnotes in Richardson (re the ancestry of John Orr of Virginia) imply the same conection, also citing GBR.
However, Fasti calls her a daughter of David not William Crawford. This could be just a slip, but if it's correct, the line breaks here. (There was a David Crawford of Drumsoy about this time, whose son became 16th of Auchinames by marrying the heiress.)