Finding a close cousin is always rewarding but sometimes confirming distant cousins is better. When a genetically-proven 3rd cousin and I identify our common 2nd great grandparents, it provides solid evidence for the whole family line beneath them. It validates my paperwork and reveals that there weren't any "accidents" in that branch of the family tree. However, when a 5th cousin and I locate our shared 4th great grandparents, a far more difficult task, then I prove a much longer branch of that family tree.
Dr. Edwin Lampitt from Missouri and I share our 4th great grandparents: James Harper, born Virginia in 1767, and Elizabeth Hopewell, also born Virginia in 1770. They moved west to Indiana where they had at least 2 children: James and Francis. James Harper Jr. was a grandfather to Emma Hethcot, who married Thomas Simpson, and was my father's grandmother.
Meanwhile, Francis Harper married John Greer and moved west to Iowa. Her granddaughter, also Francis, married Edwin Lampitt and moved out to Illinois. Their great-grandson is my 5th cousin.
This old family tree shows a couple of the generations of my Harper family ancestors, although William Washington Harper was not a direct ancestor but my 2nd great uncle.