There is confusion as to which Sarah Lyon married Joseph Bennett, but by analyzing the avaiable secondary sources, this can be determined with sufficient accuracy. 'The History of Old Fairfield' by Donald Lines Jacobus contradicts itself as showing two different Sarah Lyon's marrying Joseph Bennett. 'Lyon Memorial' by Sidney Elizabeth Lyon shows a single Sarah which partially supports Jacobus. The following four accounts were used for the analysis:

1. In Vol. 2, page 110 [Jacobus] it shows Sarah Lyon marrying Joseph Bennett on December 21, 1763. She is listed as being born June 30, 1748, and dying January 6, 1786. Her gravestone in Westport, Connecticut listes her age as 38 years, 5 months and a few days. It also lists children born between the years of 1764 and 1784. Joseph married as his third wife Sarah Sturgis who died June 16, 1812.

2. In Vol. 2, page 599 [Jacobus] it lists Sarah, daughter of James (21 Mar 1704 - 26 Mar 1752) and granddaughter of Samuel, who was born on January 1, 1745/6 and died on April 4, 1757. It then lists another Sarah for James born June 30, 1748, baptized on July 2, 1748, married Joseph Bennett on December 21, 1763, and died in Westport, Connecticut on January 6, 1786. Her gravestone in Westport, Connecticut listes her age as 38 years, 5 months and a few days.

3. In Vol. 2, page 610 [Jacobus] it lists Sarah, daughter of David Lyon (abt 1721 - 22 Nov 1764), and granddaughter of David Lyon, who was born July 4, 1747, baptized August 9, 1747, married Joseph Bennett, and died June 16, 1812. Her gravestone in Westport, Connecticut listes her age as 64 years.

4. On page 264 [Lyon] is lists a Sarah Lyon, the daughter of James (21 Mar 1704 - ) and granddaughter of Samuel, was born on January 1, 1746 and died on April 4, 1747 or 1757?. It then lists another Sarah (page 273) for James born June 30, 1748, and married Elijah Olmsted on March 17, 1769. They had several children between the years of 1770 and 1795. After their marriage, they moved to Saratoga, New York. Her death date was not listed.

From this we can determine that there were three Sarah Lyon's born in Fairfield, Fairfield County, Connecticut between 1745 and 1748. Since birth and baptism dates usually occur in church records associated with a family, it can be assured that James Lyon had two daughters named Sarah, which was not that unusual if one died young. The first was born in 1745/6 and died in 1747. Then in 1748 the second was born. David Lyon also had a daughter named Sarah born July 4, 1747 and baptized in Westport on August 9, 1747.
We also know that James' surviving daughter, Sarah, married Elijah Olmsted in 1769 and moved to New York and died sometime after 1795. This leaves only David's daughter, Sarah, as the wife of Joseph. This Sarah died on January 6, 1786 according to her gravestone in Westport, Connecticut. It was Joseph's thrid wife, Sarah Sturgis that died in 1812. Sarah Lyon's gravestone states she died at 38 years, 5 months, and a few days. This places her birth at about August 4, 1747, which would be only one month younger than her actual birth. It is also possible that the gravestone has 6 months but was difficult to read.

Joseph Bennett married Sarah Lyon on December 21, 1763 in Fairfield, Fairfield County, Connecticut. The first 8 children werel baptized in Westport, Fairfield County, Connecticut.

Sarah (bp 18 Nov 1764 - bef 21 June 1819) m. 4 May 1780, Zophar Brush
Rhoda (bp 2 Apr 1769 - aft 1824) m. 19 Dec 1787, Robert Willian Taylor
Lydia (bp 12 May 1771 - bef 21 Jun 1819) m. 8 Mar 1789, Thomas Lockwood
Priscilla (bp 7 Aug 1774 - 19 Jan. 1777)
Joseph (bp 11 Aug 1776 - 17 Jan. 1777)
Priscilla (bp 7 Feb 1779 - aft 21 June 1819) m. 26 Nov 1799, Isaac Sears
Charity (bp 26 May 1782 - aft 21 June 1819) m1?. Noah-Wakeman Bradley?, m2?. David Judah.
Martha (bp 18 Jul 1784 - aft 21 June 1819) m. 2 Oct 1803, Samuel Sears