I revisited the 1850 U.S. Census of James Old. In this census three generations of James Old are listed. In addition listed near the bottom of the James Old family is "Jane Lee" & her place of birth "Scotland". I wondered for some time thinking that this name was just a coincident, then I remembered that Mary Lee (child of John & Jane Lee and wife of James Old) died in 1850! We do not know the exact date of Mary Lee's death but it makes since that her mother would be around to console and help with the family. I think that this "Jane Lee" is Jane (Davidson) Lee, mother of Mary Lee. Also noticed only two children are listed (Anna Old & James Lee Old), these are the only children of Mary (Lee) Old/James Old.
Anna Jane Old, age 3 (born 1846) dies in 1863 at age 17, leaving James Lee Old the only survivor of this marriage with Mary Lee!!!
The 1850 U.S. Census can be found under "Latest Documents" about 12 documents down from the top of the page.