Mary Beverly Chew md. Joseph Brock (Col.) @1755

Joseph Brock, Sr. was born 1668 in England, and died @ 1743 in Spotsylvania Co. VA, md. Mary Clayton.
Their son, Joseph Brock, (Col.), born November 06, 1715, md. Mary Beverly Chew by 1755, in Spotsylvania Co. VA.

Where does Mary Beverly Chew fit into the Chew family?
I have that she is the second child of John Chew and Margaret (Beverly) Chew.
JOHN I have as the second surviving son of Larkin and Hannah (Roy) Chew, and MARGARET as the dau. of Col.
Robert Beverly, Clerk of tlie Council of Virginia
in 1679, and author of the History of Virginia, by
R. B., Gent., published in 1705.

I have that MARY BEVERLY and Col. JOSEPH BROCK, had issue: i. JOHN md. ANN CURTIS;
ii. ELIZABETH md. 1st, J. T. LEWIS, and
2d, BEVERLY STUBBLEFIELD, Or STRIBBLEFIELD;
iii. MARY md. JOHN CARTER;
iv. CATHERINE d. unmarried:

Did they have another son named Thomas Brock (d. 1825) who married Mary McCollam or McCollum?

Does any have info to confirm this line?