Anne, Here is some add'l info regarding your family from the same Blackshear document. The document is one of those "vanity" pieces, so proceed with caution. (Again, there is much information in this document regarding the German ancestry of the Blackshears - complete with stories told by descendants - which are not borne out by the actual facts.) No sources are cited, but this could provide some ideas for your search.
"James Blackshear's father-in-law, Johan Martin Franck (1682-1744), was a German Lutheran schoolmaster, who emigrated to New Bern in 1710. The great Dr. August Herman Franck (1663-1729) of Halle, Germany, philanthropist, founder of orphanages and schools for poor boys, and of the Franck Institute at Halle, wrote Cotton Mather (1663-1728) of Boston that Dr. Franck's son, Johan Martin Franck, was immigrating to America, and requested Mather to aid the young schoolmaster in getting appropriately located. But the young man had met the beautiful Civella Miller, the daughter of Jacob and Catherine Miller, and instead of locating near Cotton Mather, the young schoolmaster came with Civella and her parents, and their other children, to New Bern. Some say Johan Martin Franck married Civella in London, while others say the marriage took place in North Carolina. "The late Dr. Collier Cobb of the Unviersity of North Carolina said, in an address at an annual meeting of the Society of Descendants of the Palatines, at Kinston, NC, that: "Frank had with him his surveying instruments, and he brought along many small wares that he thought might be useful to the Colonists. He went up one bank of the Trent River and down the other, starting out with his surveyors' compass on his shoulder and his peddler's pack on his back. He returned to New Bern in less than two years with a fine estate called 'Little Germany', not far from the head of the river, with land on both sides of the Trent and with his pockets full of ready money. He was almost immediately elected a member of the General Assembly of 1712, and returned to New Bern as a justice of the peace. His sons took wives from the best that the Colony afforded; and his wife's brothers, the Millers - Jacob, John, and Philip have also had an honorable part in bulding up this and other States."