She married John Nelson, probably in Kentucky.  Their first known son, Eldridge, was born in Breckinridge County, Kentucky, in 1836.  A second son arrived in 1837 and by the time of the 1840 Federal Census, the young family was located in Hancock County, Illinois.

John Nelson was born July 28, 1812, in Hardin County, Kentucky, to Thomas Nelson and Susan Pierce.  There is circumstantial evidence, based on names and locations in 1840 and 1850, that John's parents also came to Illinois.

Isabell was named in her father's will, prepared in 1841, as Isabella Nelson.

She died January 30, 1855, probably in or near Hancock or McDonough County, and was buried in the latter county at Friendship Cemetery.

Although we have no information about John Nelson's early life, we can reasonably presume he received some level of education.  There are examples of his penmanship on notes he wrote when three of his sons married before the age of 21; John Nelson wrote with a strong, clear hand.

The known children of Isabell Roberts and John Nelson were:

i.	Eldridge C. Nelson, born January 11, 1836 (calculated from his tombstone inscription), in Breckinridge County, Kentucky.  He died October 13, 1890, probably in or near Jefferson Township, Chautauqua County, Kansas, burial in adjacent Cowley County, at North Cedar Creek Cemetery.
ii.	James Vincent Nelson, born February 9, 1837, in Kentucky, perhaps Breckinridge County.  He died November 15, 1915, in Kechi Township, Sedgwick County, Kansas, burial at Kechi Cemetery.
iii.	Dorsey Nelson, born in Illinois January 12, 1841, died June 10, 1912, at Cedar Vale, Chautauqua County, burial at North Cedar Creek Cemetery.
iv.	Mary Elizabeth Nelson, born July 9, 1843, in Illinois, died June 10, 1926 (fourteen years to the day after the death of Dorsey), in Winfield, Cowley County, Kansas.
v.	Matilda Nelson, born about 1846 in Illinois.
vi.	Winfield S. L. Nelson, born in 1846 in Illinois.  He died June 22, 1918, at Colchester, McDonough County, interment at Mount Auburn Cemetery, Colchester.
vii.	Lucy N. Nelson, born in 1851 in Illinois.  She died in 1931, probably in Buffalo County, Nebraska, and was buried at Armada Cemetery, near Miller, in Buffalo County.

Frances A. Towler was born April 3, 1834 (calculated from her tombstone inscription), in Virginia, the daughter of William and Frances Towler (often found spelled Toler).  William Towler and family reportedly came to McDonough County in 1850 or '51; daughter Frances Towler Goad joined them several years later, at which time she was either already or soon to be widowed, divorced or abandoned.

John Nelson and Mrs. Frances Goad were married on September 25, 1856.  Frances brought two children to the marriage: Albert R. and Mary Goad.

John and Frances had four known children:

i.	Robert A. Nelson, born June 1858 in Illinois, probably Hire Township, McDonough County.  He died at Macomb in December 1932, and was buried at Glade City Cemetery in Blandinsville, both in McDonough County.
ii.	Ostie Isabell Nelson, born about 1865 in Illinois.
iii.	Charles Nelson, born about 1869 in Illinois.
iv.	Fannie Nelson, born about 1874 in Illinois.  According to Teresa Hoddy, John Nelson and Isabell Roberts' fourth great-granddaughter, Fannie was present for a picture taken at Eldridge and Emily Pierce Nelson's home in Chautauqua County, Kansas, circa 1890.

Frances died March 27, 1879.  John buried her next to Isabell at Friendship Cemetery. Tombstone, marriage record and more information regarding Frances Towler Goad Nelson

 
In the early 1880s, John Nelson said goodbye to some of his children, perhaps paid a last visit to the graves of Isabell and Frances, and turned westward.  Whether he tarried somewhere along the way we do not know, but he ended up in Jefferson Township, Chautauqua County, Kansas, where son Eldridge was already living.  At least three of John's children and their families apparently accompanied him on this move: Mary Nelson Keithley and Dorsey Nelson (daughter and son of Isabell), and Charles Nelson (son of Frances).

Why did this 70 year old man climb onto a hard wagon seat for a weeks-long trip to a place he'd never seen before, leaving his home of 40 plus years and most likely realizing he'd never see some of his loved ones again?  The usual answers could be a practical need to live with those willing and able to care for an aging parent, or something purely personality driven - the desire to see one more new horizon before the end of the road.  In John Nelson's story there's yet another element: on December 17, 1881, at 69, he married Mrs. Cynthia M. Shippy of Colchester, 55, widow of Thomas Shippy.  Marriage documents Cynthia Mariah Spencer, born in New Madrid County, Missouri, on April 14, 1826, was the daughter of Isaac Spencer and Martha Adams. (Isaac would subsequently marry Keziah Welch and, perhaps, Mrs. Comfort Carroll.)  Cynthia was first married to Thomas Shippy in McDonough County about July 9, 1846.  They raised a large family while living in Tennessee Township for a number of years, apparently until Thomas Shippy died.  (This surname is found as Shippy on Cynthia and Thomas' marriage license, as well as 1850, 1860 and 1880 Federal Census records.  In the 1870 Census it was recorded as Shippey, and Cynthia's tombstone bears the name Shippey.) "Maria Shippy" was working as a housekeeper in Colchester in 1880.

Tombstone picture courtesy of Don Tharp, host of Kansas Trails, Chautauqua County, website

Not very long after John and Cynthia's marriage, he was on his way to Kansas.  We tend to think that she did not accompany him, but that they were not divorced.  A family history written years later by a second great-granddaughter who grew up in Kansas, did not mention Cynthia or even the fact that John had married a third time.  Eight months after John died, Mrs. Cynthia M. Nelson married Almond DeWitt in McDonough County. We are guessing this was a more satisfactory union for Cynthia: when she died on August 28, 1898, she was buried next to her son at Mount Auburn Cemetery in Colchester, McDonough County, under the name Cynthia Shippey, with her marriage to Mr. DeWitt also noted on the marker.  (In 1899 and again in 1902, Almond, a veteran of the war against Mexico, was admitted to the Soldiers' and Sailors' Home in Quincy.)

We may never know what transpired between John and Cynthia, but we do know he put Illinois at his back and spent about ten years in Kansas before he died on February 16, 1893, in or near Cedar Vale, Chautauqua County, and was buried in adjacent Cowley County, at North Cedar Creek Cemetery.  Panoramic view of Nelson family tombstones

Household of John Nelson
Males 0 through 4 - 2 [Eldridge, James]
Males 20 through 29 - 2 [John]
Females 20 through 29 - 1 [Isabell]
Total - 4
Persons employed in agriculture - 1

John Nelson, 38, male, farmer, value of real estate 600, born KY
Isabel, 38, female, born TN, could not read or write
Eldrige, 15, male, born KY, attended school within the year
James, 13, male, born KY, attended school within the year
Dorca, 9, female [sic], born IL, attended school within the year
May, 7, female, born IL, attended school within the year
Matilda, 4, female, born IL
W. S. L., 2, male, born IL

John Nelson, 47, male, farmer, value of real estate 1440, value of personal estate 3700,
born KY
Francis, 26, female, born VA
Dawsy, 19, male, born IL
Mary, 17, female, born IL
Matilda, 15, female, born IL, attended school within the year
Winfield, 12, male, born IL, attended school within the year
Lucy, 10, female, born KY, attended school within the year [This is the only census showing that Lucy was born in Kentucky.]
Albert [Goad], 7, male, born IL, attended school within the year
Mary [Goad], 5, female, born IL
Robet [Nelson], 2, male, born IL
Eremith Fowler [sic], 17, female, born KY

Nelson, John, 57, male, white, farmer, value of real estate 8000, value of personal estate 600, born KY, male citizen of the U.S. aged 21 or more
Francis, 35, female, white, keep house, born KY
Mary [Goad], 14, female, white, born IL, attended school within the year
Robt, 11, male, white, born IL, attended school within the year
Isabelle, 5, female, white, born IL
Chas, 1, male, white, born IL

Nelson, John, white, male, 69, widower, farmer, born KY, both parents born KY
Robert, white, male, 22, son, single, works on farm, born IL, father born KY, mother born VA
Eliabel, white, female, 14, daughter, single, keeps house, father born KY, mother born VA
Charley, white, male, 10, son, single, at school, born IL, father born KY, mother born VA
Fanney, white, female, 5, daughter, born IL, father born KY, mother born VA