Mary Blair Andrews (ca. 1759–1820) was the daughter of John Blair, associate justice of the United States Supreme Court. In 1795 she married Robert Andrews (ca. 1748–1804), the mathematics professor at the College of William and Mary (father’s and husband’s biographies in DVB description begins John T. Kneebone and others, eds., Dictionary of Virginia Biography, 1998– , 3 vols. description ends ; WMQ description begins William and Mary Quarterly, 1892–  description ends , 1st ser., 5 [1896]: 143; will in Vi: RG 12, Wills from the Treasurer’s Office; American Beacon and Norfolk & Portsmouth Daily Advertiser, 19 Jan. 1820; Richmond Enquirer, 20 Jan. 1820).

The friend who provided TJ with a copy of John Blair’s will was Thomas Eston Randolph, to whom it had been enclosed in a letter from David M. Randolph, writing from “Fighting Creek,” 25 Aug. 1815: “Presumptuous as it certainly is, for me to hazard Law-opinions, yet am I induced to differ in my construction of the enclosed will of the Honourable John Blair deceased. From the sober exercise of my simple perceptions, my convictions are, that Mrs Andrews, the surviving daughter, is intitled to the Life-Estate in the Albemarle Lands, and every thing appertain[in]g thereto at the decree of the Testator, conjointly: and, from the decree of Mr Henderson, Mrs Andrews is equally intitled to the enjoyment of the whole of the said Estate, to her death—And if (since Thomas, the Son of Jane had never any defined rights) the rule of Law, is such as to bar Thomas; it would seem that the Husband of Jane and father of Thomas, can legally inherit nothing! For, as Mr Henderson now demands a division of the Albemarle Estate: since Mrs Andrews may produce heirs, to share ‘per. Capita’ how can a division be called for under the provisions of the will, until the decease of Mrs Andrews? Hence, I have grounded my opinion: and, from a serious consideration of the several items in the will, I am persuaded that your goodness, either seperately, or in union with T.M.R. [Thomas Mann Randolph] will <not only> parden me in taking upon me to hope, that you will obtain from Mr Jefferson his deliberate opinion; and a cheerful declaration of it to the Lady in question” (RC in MHi; addressed: “Thomas Eston Randolph Esqr. Milton near Monticello Albemarle”; stamped; postmarked Charlottesville, 6 Sept.; one word and one set of initials editorially expanded).

The portion of John Blair’s will relating to the mountain plains the negroes and stock appurtenant provided that the “plantation, in Albemarle County, commonly called, The Mountain plane, together with the Slaves, and stock of every sort kept thereon, to my two dear daughters, that is to say, the one moiety thereof to Mary, the Wife of the said Robert Andrews, the other moiety thereof to Jane, the Wife of the said James Henderson, for and during their natural lives, remainder to their Children who shall be living at the time of the decease of either of my said Daughters or devisees for life, and the heirs of such children; which remainder to the Children to be per capita and not per stirpes; so that upon the death of either of my said daughters, her moiety shall go in remainder, not to her Children only but to them and the children of my surviving daughter in fee simple. Item, as by this disposition to the Children, the land, in case of many sharers, may come to be divided into such small parts, that it would be better for all parties, to sell the same and divide the money among them, I hereby authorize that to be done, even during the minority of some of the parties, if from circumstances it shall be thought adviseable” (will in Vi: RG 50, James River Company, Wills and Qualifications).