John Learwood (who I've always called the immigrant) is found in Cavaliers & Pioneers Vol 3:
Patent Book #10: Simon Knight, 171 acres, Upper parish of Nansemond Co, on head of the Honey Pott Swamp . . . adj. Col Baker & Mr Write; 16 July 1717 p.133. Importation of 4 persons: Simon Knight, Elizabeth Knight, John Learwood, Ann Persall.
It's interesting that John Leatherwood of MD died in 1716, one year before John Learwood appears in VA. I have learned that "importation" did not always or even usually mean "from the mother country/England" but could have been from any of England's other new world colonies, i.e., Bermuda, Maryland, wherever.
John Leatherwood's eldest son (Samuel, I think, b.1681) was likely the sole male heir, meaning that younger, landless sons were apt to strike off for new territories.
Interesting, too, that one descent line of Samuel Leatherwood migrated from MD to VA to SC to Lincoln Co TN & AL. These Leatherwood's also married into what appears to be some of the same families as our Learwoods. I'm still wondering if some of our "missing" Learwood/Larwood sons reverted to Leatherwood surname.