Extract from the 1870 Census:
Name: Sarah McCay
Age in 1870: 65
Estimated birth year: 1805
Birthplace: Pennsylvania
Race: white
Sex: female
Relation to head-of-house: mother-in-law
Living with: David and Phoebe Guthrie, ages 34 and 32
Home in 1870: Marrowbone, Moultrie, Illinois
Post office: Marrowbone
Occupation: keeps house
Census place: Marrowbone, Moultrie, Illinois; Roll: M593_264; Page: 79; Image: 158
Date: 5 Aug 1870

Extract from the 1880 Census:
Name: Sarah S McCay
Age: 79
Estimated birth year: 1801
Birthplace: Pennsylvania
Race: white
Sex: female
Relationship to head-of-household: mother-in-law
Living with: David and Phoebe Guthrie, ages 43 and 44
Home in 1880: Marrowbone, Moultrie, Illinois
Marital status: widow
Father's birthplace: Pennsylvania
Mother's birthplace: Pennsylvania
Occupation: none
Census place: Marrowbone, Moultrie, Illinois; Roll: T9_239; Family History Film: 1254239; Page: 428.1000; Enumeration District: 171; Image: 0111
Date: 8 Jun 1880

Extract from "History of Washington County, Pennsylvania with Biographical Sketches of Many of Its Pioneers and Prominent Men" by Boyd Crumrine, Philadelphia, L H Leverts & Co., 1882, which mentions Sarah Stoolfire:
Charles Stoolfire was a farmer who lived and died in Donegal township. His home was a farm of one hundred and six acres of land, which he purchased of George Humbaugh, Aug. 18, 1804, a part of the tract "Freedom," patented to Mark Causland Jan. 15, 1798. The homestead of Charles Stoolfire is now owned by Mr. Ralston. He had a very large family of children, eleven of whom reached mature age. Joshua married Margaret Miller. Jacob, who married Isabella Rogers, and Margaret, the wife of Alexander Hunt, both live in Licking County, Ohio. Catharine married Jacob Grear, and went to Hancock County, Ohio. Lydia also married, and lives in Ohio. Sarah became the wife of James McKey [sic], and removed to Illinois. George married Nancy Madden, and lives in this State. David went to Kansas, where he married, and Susan, who became Mrs. Joseph Ritchie, lives in Ohio. Nancy is Mrs. John Rush, and resides near West Middletown, in this county. Eliza died single. Mrs. Daniel Sheller, Mrs. Ruth Hayburn, and other residents in this vicinity are lineal descendants of Charles Stoolfire.

Death notice from the "Herald" of Sauk Centre, Minnesota dated 7 Apr 1882:
Mrs. Sarah S. McKay died at the residence of her son in this village last Wednesday. Mrs. McKay was a very active woman for her years, being 82 years old. She died of asthma.

Children:
(1) William M McCay
(2) Calvin McCay
(3) Charles S McKay
(4) Matilda C "Tillie" McCay
(5) Susannah R "Sue" McCay
(6) Phoebe McKay
(7) Catharine "Kate" McCay
(8) Elizabeth McCay
(9) Mary W McCay
(10) Samuel C "Sam" McKay
(11) Joshua S McCay
(12) Thomas Carson McCay.