The Clyde Groff research proves that David Eby was not a son of Theodorus. This is a large family mystery! See notes on David Davis Ebi.
The following notes are included from The History of the Eby Family by Ezra E. Eby excluding the reference to him being a son of Theodorus.
David Eby was born in May 1701. He learned the carpenter trade in his young days, but in after years he followed that of blacksmithing and farming. He was married to an English girl (of Quaker descent) by the name of Maggie Davis. They had a family of five children, two sons and three daughters. Two of the daughters died in infancy and the other was married to a Mr. Clemson, an Englishman. Of the two sons, Samuel Davis Eby and David Davis Eby, we have a record of but David Davis. Samuel Davis left home and went West in 1763. A year thereafter his parents received a letter from him in which he stated that he was well contented where he was and that he shall never return home again. HEF p. 51
David Davis Ebi:
"We, the authors of the Eby Report, have long sought the correct relationship of the man known as David Davies Ebi. As genealogists and researchers, we have never doubted his existence, only his generation in relation to the other Ebys in America and his ancestry. Historians have given the date of birth as Jan. 1, 1742 which is taken from the tombstone in the Nimishillen Cemetery in Stark County, Ohio. It is possible that David Davies Ebi, Sr. was a descendant of Heinrich Eby who immigrated to America in 1732, we know very little of this individual. Or he might even be from the family of Jacob Eby, son of Andreas Eby, who we have just added to the family. We still know of no documentary evidence to connect this family with the Ebys of Lancaster County, PA". - Groff Vol II/1
When but a young man he left home and went to Virginia, where he sojourned until the commencement of the Revolutionary War, in which he enlisted and remained a soldier until the war closed and the Independence of the Thirteen Colonies was established. After the close of the war he settled in Virginia. To whom he was married was not ascertained, but it is known that in the year 1807 two of his sons settled in Stark County, Ohio, to which place he followed them a few years later. He settled down near his sons and resided there until his death, which took place in 1823. This famous champion of Independence attained unto the advanced age of 81 year. HEF p. 52