John Rockwell (1788-1862) [R125 in edition 1, R121 in edition 2]: Further details on his descendants, from Phoenix 2069-70 and Boughton, p.377 and 485:

Son Sylvester Bird Rockwell and his wife Elizabeth DeLong had three daughters [PW 2069, BRK 377]:

1. Beaumelle Rockwell, b. 27 April 1840 at Cornwall, Vt.: married 12 June 1866 at Middlebury, Vt., Ethan Allen Sturtevant, a lawyer, born at Weybridge, Vt. on 21 Feb. 1839, son of Milo and Lucy (Taft) Sturtevant. He graduated at Middlebury College in 1863, and at the University of Michigan Law School in 1864. They were living at Middlebury, Vt., in 1876. He died, and she married, second, E. W. Peet, and resided at San Jose, Calif., in 1893. Children [PW 2408]: Fanny Beaumelle Sturtevant, b. 21 Aug. 1868 at East Saginaw, Michigan; died there 7 Aug. 1869; and Mary B. Sturtevant, b. 9 Sept. 1871 at Middlebury, Vt. I found none of them in 1880.
2. Frances Viola Rockwell, b. 11 Oct. 1846 at Shoreham, Vt., married at Middlebury on 1 Dec. 1868, Ezra Brainerd, who was born at St. Albans, Vt., on 17 Dec. 1844. Their children [PW 2408-09, BRK 485]: Elizabeth DeLong Brainerd (b. 21 march 1870 at Middlebury; resided there unmarried in 1895); Bertha Brainerd (b. 12 Nov. 1872 at Middlebury; resided there unmarried in 1895); Gertrude V. Brainard, b. 5 Aug. 1875; resided there unmarried in 1895); Ezra Brainerd Jr (b. 26 Aug. 1878 at Middlebury); Miranda Stromahan Brainerd (b. 24 Jan. 1881 at Middlebury); and Alice Beaumelle Brainerd (b. 29 May 1883 at Middlebury). Boughton includes a lengthy summary of the career of Ezra Brainerd, who became the 8th President of Middlebury College on 17 April 1886.
3. Alice Bird Rockwell, b. 25 April 1852; resided unmarried at Middlebury in 1891.

Son Simeon Sperry Rockwell and his wife Mary Beulah (Jones) had two daughters:

1. Mary Angeline Hephzibah Rockwell, b. 12 July 1840 at Cornwall; married there, 27 August 1867, Edward Octavius Porter, a physician and surgeon, who was born 12 Dec. 1836 at Cornwall, son of Dr. Marcus Octavius and Julia (Chipman) Porter. He received his M.D. degree from Castleton Medical College in 1859. They resided at Cornwall in 1891. In the 1880 census, Edward O. Porter, "Dr. of Med." was enumerated while a boarder in the Carlton J. Moore household in Middlebury.
2. Cornelia T. Rockwell, b. 11 Oct. 1850 at Cornwall; married there, 19 Feb. 1873, Harrison E. Sanford, a farmer, born at Cornwall 29 Jan. 1847. They resided at Cornwall in 1891. The 1880 census shows them living in her father Simeon's household in Cornwall; Harrison was engaged in farm labor, probably on Simeon's farm. He and Cornelia apparently had two children:
   1. Una Rockwell Sanford, b. 9 Jan. 1874 [PW 2409]
   2. Beulah M. Sanford, 3 in the 1880 household.
   Oddly, in 1900, when the Sanfords were still in Cornwall, with Simeon and his second wife Lucy in the household, Cornelia reportedly had had no children. The Whitney genealogy is clear that Una was her child, and the 1880 census identified her and Beulah as Simeon's granddaughters. Maybe they had died (as the census also reports no living children).