Brown siblings

James Monroe Brown 1815 -1882 married Susan Pearson Squires 1815-1860, Susans twin Seth Pearson Squires 1815- married Nancy Brown 1822-1898, Seth and Susans brother Bela married Jennette Brown d.1872. They were all for awhile jewelers in NYC. Some are buried in Sleepy Hallow and James Brown born in Westchester County, Squires from Conn. Would like to know if the Browns were siblings as I do not have James parents, but do have parents of Nancy.
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