His birth is confirmed within the book "The Ark and Dove adventurers" (pg. 50) written for the Ark and Dove Society by George Ely Russell and Donna Valley Russell. However, the identification of his mother is apparently contested:

http://books.google.cl/books?id=mq5sidFiyHUC&pg=PA45&lpg=PA45&dq=%22Charles+Calvert%22+%22Stafford+County%22+1691&source=bl&ots=Z_qfB-ROo2&sig=5ECE2f64kVldCt9Hkv_HiiLGlak&hl=es&ei=OHmuTKS5A8G88gbtq4H1BA&sa=X&oi=book_result&ct=result&resnum=2&ved=0CBoQ6AEwAQ#v=onepage&q=%22Charles%20Calvert%22%20%22Stafford%20County%22%201691&f=false

George Calvert, son of George and Elizabeth (Doyne) Calvert, born c.1694 and died 3 December 1771 in Prince William County, Virginia. He married first ther or in Stafford County Sytha Elizabeth Harrison, who died by 1741. He married second c1741 Esther (Unknown).

In 1771, Obed Calvert signed the administrator's bond of Esther Calvert, widow.[288]

Children of George and Sytha (Harrison) Calvert, as reported by O'Brien with no documentation:

• 1. Obadiah Calvert b. c1719, d. 1805 Prince William County, VA, m. Gosling [289]
• 2. George Calvert d. 1802
• 3. John Calvert, b. Stafford County, d. 1788 Prince William County, VA.
• 4 William Calvert, b. 22 February 1732
• 5. Humphrey Calvert, d. 1802 Stafford County, VA.

References:

[288] John Bailey Calvert Nicklin, "An Index of Calverts (1664-1799), Genealogy of Virginia Families from the William and Mary Quarterly Historical Magazine (1982), 1:542-554.

[289] O'Brien, 8.