I believe that Elizabeth Mossom married John Reynolds not William Reynolds and they had no children.
I think her sister, Susannah married William Reynolds.

I know many researcher have Elizabeth Mossom married to William Reynolds with 10 children;
James Reynolds born 1750 in Stafford, Albemarle County, Virginia
Thomas Reynolds born 1752 in Stafford, Albemarle County, Virginia,
Aaron Reynolds born 1 December 1753 in Stafford, Albemarle County, Virginia
Susannah Reynolds born about 1755 in Stafford, Virginia,
Elizabeth Mossom Reynolds born 13 February 1757 in New Kent County, Virginia,
Isaac Reynolds born 1760 in Albemarle County, Virginia,
Nathaniel Reynolds born 25 November 1762 in King William County, Virginia,
William , Jr. Reynolds born 1763 in Albemarle County, Virginia,
John Reynolds born about 1765 in Virginia,
Bartemus Reynolds born 25 August 1769 in Virginia.

I have three good reasons and sources.

1. Elizabeth's tombstone states that she died December 24th 1754, so she couldn't be the mother of the last 7 children. Her tombstone is located at Saint Peter’s Church, New Kent County, Virginia

HERE
Lies interred the Body of
ELIZABETH, wife of Mr JOHN
REYNOLDS, of the City of Briftol
Marriner, & Daughter of the Revd
Mr DAVID Mossom Rector of this
Parifh, She Departed this Life
December the 24th 1754
Aged 30 years

2. Records found in William and Mary College Quarterly, Vol. 5, No. 1 page 67.
Mossom Bible - I have been favored by Mrs. Calvin Perkins, of Memphis, Tenn., with a view of the Bible used by Reverend David Mossom……
Elizabeth daughter of David and Elizabeth Mossom was born Friday September 21, 1722 near ten in the morning and baptized Sunday September 30, 1722.
As shown elsewhere…. The youngest child above of the first marriage, Elizabeth Mossom, born in 1722, married Captain William Reynolds, owner of a vessel plying in the tobacco trade. Their daughter, Elizabeth, married Richard Chapman, Jr., and the births of their children are entered in an old prayer book which I have been permitted to see: Jane Chapman was born 29 Feb. 1776. [Mrs. Price, of Hanover, d.s.p.] Reynolds Chapman was born 22 July 1778 died February, 1844. Succeeded George C. Taylor as clerk of Orange County in 1802. He married Rebecca Conway Madison, daughter of General William Madison and his wife Frances Throckmorton. One of their children was Judge John Madison Chapman, who married August 3, 1841, Susannah Digges Cole. Johnson Chapman was born 26 Dec. 1780. [Signed] Sunday March 1781, Richard Chapman.

3. Richard Chapman Bible
Susannah Mossom Chapman departed this life Saturday 23 day of May 1789 about 10 o’clock in the morning in the 4th year of her life.

After reading Richard Chapman Bible (Elizabeth Mossom Reynolds’ husband) I saw where they had a daughter named Susannah Mossom Chapman. I believe she named her after her mother, making her mother Susannah Mossom not Elizabeth Mossom.

This is how she named her other children:
Jane Chapman (after her mother in-mother)
Reynolds Chapman (after her family name)
Johnson Chapman (after her mother in-law maiden name)
Susannah Mossom Chapman (after her mother)