I think this is Mary Boothby
The evidence is amassing that Elizabeth M. Hockman/Earhart was not born to John Earhart and Margaret Shotwell. Here is what I have found so far.
1. Elizabeth Hockman, age 4, was enumerated with the John Arehart household in the 1860 census (taken 6/28/1860, which according to her daughter on the death cert would have been 11 days after her 5th birthday but if the census taker was sticking to 1 June as the date of record then 4 is accurate). Also in the household were Margaret Arehart, Tillford Arehart, William Arehart (later AKA Samuel), and Ruth Shotwell, Domestic.
2. Elizabeth M. Earhart was also enumerated with the John Earhart household on the 1870 census (15 years old, listed as helps mother) along with William S. Earhart (age 18, works out, Farm), and John C. (age 6, attends school). It seems likely that Elizabeth/Mary lived with the Earharts until she married at 18 in 1873. This was a very rural area, and the Earharts lived on a farm described as a mile or so off the main road, so I haven’t figured out what other records might show her presence at the Earharts between the two census points. It seems unlikely that there is a city directory that would include the household.
3. Tilford Earhart lived at home in 1860 and up to the time he enlisted in the Army in the Civil War in August 1862. He died at home in 1866. In 1888, Margaret made an application for a mother’s pension based on the death of her son due to his military service. In 1892 there was a special hearing on this application and statements were again taken.
4. In her application for the pension, Margaret Shotwell Earhart did not ever mention a daughter. She said in her sworn statements that she had borne two sons, one of them Tilford E. Earhart who had served in the Civil War and the other John Charles who was born during that War. She clearly described the family as consisting of her husband, herself and the 2 sons.
5. John Earhart’s statement in the pension application process also did not mention Elizabeth (or any daughter) but did also mention his sons.
6. The affidavits of 2 other individuals mentioned a nephew (and one named him as Samuel) who lived with John and Margaret and helped on the farm. Margaret herself described her nephew Samuel as having stayed on and helped them around the farm until he was a young man although he had no legal obligation to do so.
7. At least one of the affidavits mentioned that Margaret had required “girl help” over the years (perhaps due to ill-health) but at times not had it (couldn’t afford it). I’m guessing that “girl help” meant help with the work on the farm usually done by Margaret or any woman.
8. In no description in the pension application of either Tilford’s death or the circumstances the family was in at that time was Elizabeth mentioned. She would have been 9-10 years old at the time of his death in 1866.
In the early 1850s Ohio law directed that township trustees were responsible for the care of impoverished and destitute children and orphans. Such children were placed in either institutions for the poor or with individual families to whom they were indentured. Based on abstracts of the indentures of Green Creek Township, Sandusky County (found on the R.B. Hayes site) , children as young as 4 weeks old were legally indentured often to the age of 18. Thus it is possible that Elizabeth might have been placed with the Earharts if she were orphaned or her parents were unable financially to take care of her.
9. In registering the birth of their son M. K. Boothby in 1879, the parents were listed as Alexander Boothby and E.M. Hockman. Their other children that I have found registrations for are all listed with her name as Earhart, although I have not found all of the children and the ones found were the later-born ones. She was also married giving her name as Earhart.
10. Confusingly there is a Hockman family in the same close area with a daughter named Elizabeth who was born about the same time as my ancestor. Luckily, the 1870 federal census sheet shows both the John Earhart and the Delitha Hockman households within a few families of each other. Thus I am pretty sure that there were in fact 2 different Elizabeth Hockmans.
11. The only Hockman household to show up on the 1850 censuses in either Brown County or neighboring Clermont County Ohio besides the David Hockman family later the Delitha Hockman family, was a William (age 21) and Cynthia A. Hockman (age 18). I have not yet found them in the 1860 census nor subsequent ones.
12. I have not found any record of the birth of a female born to a Hockman in Ohio in 1855, although there was not state-wide mandated reporting of births until the early 1900s. Brown County did not register births until 1867, and although Clermont County registered some births from 1856 on, there is no Hockman birth found by search on familysearch.org. No luck finding a Boothby family Bible which might have included Mary’s birth information.
I conclude at this point that Mary Elizabeth (or Elizabeth Mary) was born to a Hockman, taken in at an early age by John and Margaret Earhart and that she took their name whether there was any formal or legal relationship with them. Still to be searched: court records, will/probate records, school records if they exist, church records if they exist. My quest is not over, but some progress has been made.