My parents and uncle joined the Church of Jesus Christ of Latter-day Saints in 1973; I consider them my "pioneers." In 1975, my dad and uncle's maternal grandmother Adina Keithler joined; she was followed by my dad and uncle's parents in 1976. For a few years I labored under the delusion that we were the first Church members ever in our family.
This was proven wrong in 1980, by the publication of Steinhilber. From it, we learned that Adina's grandmother, Lena Steinhilber, joined the Church in 1878. Since the author of the book, a distant cousin, wrote rather unfriendly things about the Church, we weren't sure how much of it we could believe. Just a few years ago, I found that Lena's sister, Anna Maria Roller, was also baptized in Germany during her lifetime, which sealed the deal for me.
Last November, I found another family Church member - Almon Bathrick. He and his family were natives of New York state and eventually made their way to Nauvoo, Illinois, the last place we Mormons were kicked out of. On the early records of the Church, he is found as a missionary, called to serve in Illinois. This was particularly exciting to my uncle, who spent two years as a missionary in the Chicago, Illinois mission - again, mistakenly thinking he was the first member of our family ever to do so.
And just now, I found the autobiography of another early family member who belonged to the Church, Franklin Alonzo Robison, a descendant of my Proctor family. Franklin's parents were also natives of New York and eventually came west to Utah; he was the husband of several wives (one named Isabella Eleanor Pratt, daughter of Parley P. Pratt, a prominent figure in LDS history) and the father of 29 children. Wow.
I guess this Mormon stuff must run in my family.