Sources:

1. Records of descendants/researchers of this family
a. Chuck Downen, descendant of Ione Sedgwick and Moses Hart
b. Ione (Sedgwick) Hart, an undated 2-page personal history in her hand

2. Census records, any of those indicated.

3. Ohio, Hamilton County Probate Court Marriage Records
a. Vol 4 (Restored), includes 1834, filmed on LDS FHL US/CAN Film 344452 image here

4. Cemetery records for Louisville Cemetery where Lucinda Sedgwick is buried
I found them at Salt Lake City on Saturday, July 20, 2002. What did I do with those notes?

5. Floyd County, Indiana Index to Marriage Records R-Z Book 1 Vol 4 1845-1920
found at GenealogyLibrary.com, also available LDS Film 1266794 Items 6-7
these records:
Groom/BrideSpouseDate of MarriageBook/Page
Sedgewick Thomas DPricilla TuleyJune 5 18615/259
Sedgewick RoseJames BruckerNov 12 189110/72

6. Military Service or Pension Records
a. Pension Records of Thomas Duncan Sedgwick, complete file obtained by Chuck Downen from NARA

7. American Civil War Soldiers an Ancestry.com database

8. Death Certificate of Thomas Duncan Sedgwick Jr image
found at Ancestry.com "Tennessee, Death Records, 1908-1951"

9. California Death Index California Death Index, 1940-1997
an Ancestry.com database
this record:
SEDGWICK PRISCILLA
b. 12 Aug 1903 Texas d. 12 Mar 1946 Los Angeles County MO:-- FA: SEDGWICK

10. Arkansas, County Marriages Index, 1837-1957
an Ancestry.com database
this record:
Name: T D Sedgewick; Residence: Memphis, Tennessee
Spouse's Name: Pearl Burgett; Spouse's Residence: Seyppel, Arkansas
Marriage Date: 28 Jul 1896; Event Type: Marriage Bond
FHL Film Number: 1020227

11. Rootsweb Marriage Database
this record:
NameYearSpouseCountyState
Sedgwick Chas T;1902 Mary V. Miller LamarTX

12. Texas Death Index, 1903-2000
an Ancestry.com database
this record:
NameCountyDateFile Number
Sedgwick Charles P Tarrant 4-25-46 19665

13. Washington State Archives - Digital Archives
this record: http://www.digitalarchives.wa.gov/Record/View/BDB632825C3AD81CED4AC3390A9C86C4
  Da Reference Number: {CA30F5D3-8DF4-4225-959C-26546D97C1B0}
  Image Number: 712
  Document Number: 99
  Document Reference Id: 221
  Name: Ione Sedgwick Hart
  Date Of Death: 29 Jul 1914
  Age: 75
  Gender: Female
  Father Name: Sedgwick
  Mother Name: Knaught
  Batch Id: 275617
  Batch Locality: Washington, United States
  Death Place: Aberdeen, Chehalis, Washington
  Mother Name Surname: Knaught
I don't have any idea why her mother's surname would be listed as Knaught.

Questions? Have more data? genealogy@sedgwick.org