John Sedgwick [Meriton Sidgwick / Elizabeth Burdon]
descendant of George Sidgwick of Brompton by Northallerton (c. 1600 - ?).
b. abt 1803, England
d. November 1, 1858, Saint Louis, St Louis, Missouri2
bu Saint Louis, St Louis, Missouri, Bellefontaine Cemetery
m. December 15, 1827, Brompton By Northallerton, Yorkshire, England, Mary Todd4
immigrated to Pennsylvania abt 1836, to Iowa bet 1844-1850, to Missouri bet 1850-18581

Mary Todd
b. abt 1806, England

Census records:

1850 IA Linn
Widow Mary:
1860 MO St Louis, Saint Louis
1870 MO St Louis, Saint Louis
1880 MO St Louis, Saint Louis

Found originally in census records, this family appears also here: http://www.sedgwickuk.org/uk/places/durham/george1600/sedgwick-john1805.html

Two Mary's Sedgwick died in St Louis in the 1880's.2 It is likely that one of these is John's wife.

Children [assumed from census data]:

Anne Sedgwick
  b. abt April 1829, Yorkshire, England
  ch May 2, 1829, Brompton By Northallerton, Yorkshire, England4
Elizabeth Todd Sidgwick
  b. abt March 1831, Yorkshire, England
  ch March 27, 1831, Brompton By Northallerton, Yorkshire, England4
Eleanor Sedgwick
  b. abt August 1833, Yorkshire, England
  ch August 21, 1833, Brompton By Northallerton, Yorkshire, England4
Dulcibella Meriton Sedgwick AKA Duley, Belle
  b. abt January, 1835, Yorkshire, England
  ch March 4, 1835, Brompton By Northallerton, Yorkshire, England4
  m. May 20, 1867, St Louis, St Louis, Missouri, George L Fortune3
Georgia Rebecca Sedgwick
  b. November 1836, Yorkshire, England
  ch November 27, 1836, Brompton By Northallerton, Yorkshire, England4
  d. aft 19201
  m. Unknown Herd
Lorenna Sedgwick AKA Laura
  b. abt 1840, Pennsylvania
Mary Anabella Sedgwick AKA Mollie
  b. November 1842, Pennsylvania
  d. aft 19201

Dulcibella and George Fortune appear:

1870 MO Jackson, Kansas City
They are divorced by 1880; George appears in Denver, Belle appears:
1880 MO St Louis, Saint Louis
1900 IL Cook, Chicago
1910 CA Los Angeles, Los Angeles

Georgia and Mary appear with mother through 1880 then:

1900 MO St Louis, Saint Louis
1910 MO St Louis, Saint Louis
1920 MO St Louis, Saint Louis

Sources:

1. Census records, any of those listed.

2. St. Louis City Death Records, 1850-1908
an Ancestry.com database
These records may all be this family:
Sedgurk, John, b. England, d. 01 Nov 1858, Vol F pg 238, Cemetery: Bellefontaine
Sedgwick, Luella, b. St Louis, Missouri, d. 06 Oct 1860, Vol J pg 115, Cemetery: Bellefontaine, address: Broadway
Sedgwick, Mary, d. 25 Mar 1885, Vol 17 pg 3, address: 3717 Cass
Sedgwich, Mary, d. 26 Jun 1889, Vol 23 pg 104, address: 316 S 15th

3. St. Louis, Missouri Marriages, 1804-76
an Ancestry.com database
Dulcibella Sedgwick, George L Fortune, 20 May 1867, Volume/Page: 12-607

4. Church of England. Chapelry of Brompton (Yorkshire) Parish registers, 1593-1915
Microfilm of originals at the County Hall, Northallerton
LDS Film 0894238 christenings at Brompton By Northallerton, Yorkshire, England
These children of John Sidgwick/Sedgwick/Sedgewick and Mary:
  ANNE SEDGEWICK, Christening: 02 MAY 1829
  ELIZABETH TODD SIDGWICK, Christening: 27 MAR 1831
  ELEANOR SEDGWICK, Christening: 21 AUG 1833
  DULCIBELLA MERITON SIDGWICK, Christening: 04 MAR 1835
  REBECCA SEDGWICK, Christening: 27 NOV 1836
LDS Film 0894239 marriages at Brompton By Northallerton, Yorkshire, England
  JOHN SEDGEWICK, MARY TODD, Marriage: 15 DEC 1827
Questions? Have more data? genealogy@Sedgwick.org