Thirza Johnson was born 1780 in Massachusetts. She id the daughter of William Johnson and Anna Calkins. Thirza married Armon Lathrop in Canaan, Columbia New York. They moved to Sangamon County, Illinois.
Familysearch. org: New York Probate Records, 1629-1971. Oneida County. WILLS 1798-1829 Vol. 1-3 Page: 242. Will of William Johnson. PAGE: 244" Bequeath unto my daughters, Thyrza, wife of Armen Lothrop; Lucretia E., wife of Charles Wylie; Mary B., wife of John Foot; Ashsah, wife of Samuel Pierce."
Huntington, E.B (Elijah Baldwin). "A GENEALOGICAL MEMOIR OF THE LO-LATHROP FAMILY IN THIS COUNTRY: Embracing The Descendants, as Far as Known, Of The Rev. John Lothropp, of Scituate and Barnstable, Mass., and Mark Lothrop, of Salem and Bridgewater, Mass., and the First Generation of Descendants of Other Names. 1884, Publisher: Ridgefield, Conn., M. Huntington. (PAGE 128-"#700 Armon-born in 1777, and married in Canaan, Thirza Johnson. They settled in Pittsford, N.Y., and removed in 1818 to Sangamon County, Ill., and had a large family.")
(SON) Armon Lathrop, Illinois Probate Records, 1819-1988, Effingham Wills, 1849-1857. Vol A, . "I also give my beloved Mother Thirsy Lathrope a sustenance her life time out of my property" Page No. 7
Febessa Lathsafe, (1850 Census) Effingham Co., Illinois/ b. 1780 Mississippi. AGE: 70 ( I believe this is Thirza living with her son Armon in Effingham Co., Ill. She is mentioned in Armon's Will in 1852, "my beloved Mother, Thirsey Lathrope".)