Knowing that Jane had originally married a Sparks, the most likely candidate would have been someone living close to her family, such as Isaac's immediate neighbor Matthew Sparks. Out of Matthew Sparks' five male children, his youngest son John born circa 1800 seems to be the most likely to fit the bill. John Sparks makes his first appearance on the Surry County federal census in 1820 with his household information seeming to indicate that he was a relative newlywed and only having one daughter under the age of 10. This daughter I believe to be Nancy Caroline Sparks who was born in North Carolina on March 25, 1819. What is interesting here is that on the very next day, John's father Matthew wrote out his will dated March 26, 1819. A series of deeds can be found in the county dated two days prior that show Matthew giving various amounts of land to each of his sons, with his youngest son John receiving 50 acres next to his brother Joel. If you'll remember, this was the same Joel Sparks who purchased land from Isaac Jones in 1826. There is no record of John ever selling this particular piece of land, but a deed does exist dated August 26, 1825 showing him selling his entire rights to the estate of his father for $200. I've noticed that this action has prompted researchers with the Sparks Family Association to describe it as possible "contemplation of moving away from Surry County." I couldn't agree more because he can't be found on the 1830 Surry County census and it wasn't long after 1825 that Isaac's family left the area for Tennessee. Furthermore, out of all of Matthew Sparks' children, male or female, John has been the only one to remain a relative mystery to Sparks Family researchers. In my experience, a situation like this is often indicative of a person being absorbed into a different family through marriage which is exactly what I think happened here.
The only other child known to exist from Jane Jones' marriage to a Sparks is her son Burrell J. Sparks who was born in North Carolina around 1822. It is still unknown as to what became of Jane's first husband, although based on the rest of the family's movements and her subsequent 1834 marriage to John Jeffrey, all signs would seem to indicate that he died in Tennessee and most likely in Lincoln County. The 1830 Census for Lincoln County also seems to indicate that John Jeffrey had a prior marriage before marrying Jane. His listing shows him as being married and having two girls and two boys all under the age of 10. I have yet to be able to determine the identity of John's first wife or any of these four children. This prior marriage also produced a fifth child named William Tolley Jeffrey (1832-TN) who is often mistakenly attributed to Jane Jones, considering the couple didn't marry until 1834 in Kentucky.
In keeping with the tradition of strange marriages within the Isaac Jones clan, it's very interesting to note that Jane Jones is actually one of my maternal 5th great grandmothers. Kind of odd considering her father Isaac is my maternal 5th great grandfather as well, and her brother Burrel was my maternal 4th great grandfather. This little bit of genetic mathematical trickery is courtesy of Jane's daughter Nancy Caroline Sparks who ended up marrying Thomas G. Bizzell in Calloway County, KY on March 29, 1836. Thomas and Nancy's daughter Margaret Jane Bizzell married my great (x3) grandfather John Logan Jones, son of Jane's brother Burrel. In simpler terms my great (x3) grandfather married his aunt's granddaughter. How's that for keeping it in the family?
With Jane now married to John Jeffrey, the couple together would have three children: Sarah J.(1835), Samantha E. "Amanda"(1838), and James Nix (1845). I tend to get the impression that Jane shared a particularly strong bond with her brother Burrel, with her having named her oldest known male child after him and in later years allowing her daughter Amanda to marry her first cousin and Burrel's son, Marion Alexander Jones.
Jane's marriage to John Jeffrey would come to an end with her death sometime prior to 1870. Evidence of her passing can be seen in her husband's eventual marriage to Francis Belle "Tennessee" Byars. I have yet to locate a marriage record for this union so the exact date is unknown to me. Born in 1846, Tennessee happened to be 39 years younger than John Jeffrey and together the couple had five children that I'm aware of: Ada P.(1871), Etna O.(1873), Judge Boone (1875), Stephen A.(1877), and Robert J.(1880). John Jeffrey would end up dying on September 22, 1885 followed by his wife Tennessee on September 21, 1899. John and Tennessee are buried in the Jeffrey Cemetery with marked graves and I expect his first wife Jane Jones is also buried there in an unmarked grave.