Squire Brown, born 1808, Virginia, resigned from the MSG on Dec 10, 1861 likely due to age, infirmity or illness. He would have been really long in the tooth to keep up with a Cavalry unit through the winter. He did obtain 80 acres in Phelps Co Mo in 1857 per BLM records. The best info I could find on him comes from his find-a-grave entry: http://www.findagrave.com/cgi-bin/fg.cgi?page=gr&GRid=67927842
. He must have been a bit of a character. A trip to Cedar County to look at his probate file is likely needed to determine his real date of death.