In looking for more info on this Robert's parents, I found this site:
https://www.ncgenweb.us/richmond/desrichanderson.pdf
which shows this genealogy:
Generation No. 1
1. RICHARD1
ANDERSON I was born 1585 in Pendley, Hertfershire, England, and died Aft. 1635 in Williamsburg,
Prince William, VA. He married ELIZABETH HAWKINS 20 Dec 1611 in London, England. She was born 21 Mar
1584 in All Honey Lane, London, England.
It shows their sons as:
Children of RICHARD ANDERSON and ELIZABETH HAWKINS are:
i. JOHN2
ANDERSON, b. 1614, London, England; d. Gloucester, VA.
ii. REVEREND RICHARD ANDERSON II, b. 1615, London, England; d. 1662, Gloucester, VA.
iii. THOMAS ANDERSON, b. 1616, London, England; d. 1650, Gloucester, VA
Now, rather than listing this Robert Anderson as Rev. Richard's son, it shows Robert as the son of Richard's brother John - not the brother Thomas listed on Robert's marital info in the documentat attached under Cecilia's Media tab:
Child of JOHN ANDERSON is:
3. i. ROBERT3
ANDERSON, SR., b. 1645, York, VA; d. 1712, New Kent, VA.
So, depending on where you look, Robert has each of the brothers listed as his father! Geni shows Rev. Richard, the martial info shows Thomas, and this link shows John.
So rather than finding answers as to whether Thomas or Rev. Richard was actually Robert's father...now their brother John is thrown into the mix!