Davis Cousins (getting closer)

What's so important about finding cousins? I've never known any Davis cousins because grandpa Davis was an only child of Robert Andrew Davis and Lennettie Cowley and Robert ran away from home at age 14. He was born in Missouri in 1879 and married Lennettie in 1919 in Portland, Oregon. He had a twin brother that grandpa Davis had met twice when he was young, but he could not remember his name exactly. He thought it was a different name, but could not remember it. I remember helping look through reels of film trying to locate a family where there was twin boys born about 1879 with a head of household named Jim or James Davis. We had found from the Social Security Administration that his father's name was James Davis. He had also listed his mother's name as Martha Davis. Eventually, when I was in college I found a family in the 1880 Missouri census that just might fit. The father's name was James Davis, but the mother was Emily C Davis. There was a step daughter named Martha and several other children with the last two being Robert and John, twins born in 1879. Over the years I have pieced together little bits of information and just recently found that the twins names were Robert Andrew and John Jackson. So maybe Robert's twin went by the name of Jackson, which would certainly have been a different name. Then I have found that the family had one more son named Benjamin Harrison Davis born in 1889, the same year that Benjamin Harrison was elected President of the U.S. Apparently, the Davis' were very patriotic, naming their twins after Andrew Jackson and their last child after the recently elected president.
So, now I have discovered that Benjamin Harrison Davis was baptized in 1931 and sealed in the Arizona temple to Marie Halvorsen in 1946. I had found that he had at least three children that have all passed away, except yesterday I found out about another child named Joseph Davis that might still be alive. I got his email from a man whose mother was Benjamin Harrison Davis' step daughter from Marie Halvorsen's first marriage. He thought that Joe Davis, as he referred to him, was still alive. I, of course, immediately e-mailed him and at this moment am waiting to see if he will reply. I will keep you all posted.
So, why is it so important to find cousins? Because it is an important way to tie up loose ends in our genealogical lines. I feel sure that there are a lot of my cousins out there and that one or more will be able to flesh out our ancestors. So, I will continue to pursue this search, no matter what happens with this latest find. When President Hinckley initiated this New Family Search, one of the most important aspects of it was to be the ability of connecting up with our cousins to assist each other in this immense task of finding our ancestors and getting their work done for them in the temple.