In 1857 he married Charlotte M., daughter of Dr. W. Y. McCoy, one of he first practicing physicians of Smethport, which union was blessed with three children:  William O., C. Aline (now Mrs. Dr. Lewis H. Robinson, of Brooklyn, NY) and Mary E. (now Mrs. Charles Bosworth, also of Brooklyn, NY).  William O. married Miss Julia Lightbody, and is also a resident of Brooklyn.  Mr. Hamlin is a member of McKean Lodge, F. & A. M., No. 388; of Bradford Chapter, R. A. M., and Trinity Commandery, K. T.  He is a Democrat, but not a politician, devoting his time and energies to business cares.  He and his family are members of St. Luke's Episcopal Church.  The foundation and prosperity of the church afford an example of the reward of twenty years of untiring labor by Mr. and Mrs. Hamlin, who maintained the Sunday school and church affairs in general, from 1857 to about 1880, when St. Luke's had grown to be a strong parish, and since then it has become one of the largest and most flourishing in the county.