William's Whereabouts

     The year was 1850 and I thought I knew where my great-great-great-grandfather, William H. Davis was living.  According to the 1850 U.S. Federal Census I looked at, there was an 18 year old William H. Davis living with Edwin and Adelia Bartlet in Marlborough,NY.  I had guessed or actually assumed that this William H. Davis was my g-g-g-grandfather and was living with his sister and brother-in-law because a few yars later he named his daughter Adelia.
     I recently made a connection with a descendant of William's brother, Ferris.  It is this descendant, John Davis who confirmed my assumptions about William's brothers.  He also mentioned an 1850 census which shows William living with his siblings and parents Charles and Susan.  The last name is spelled wrong which is why I never found it.  The 1850 census I found has William H. Davis living in Marlborough,NY,  age 18, born abt 1832.  The 1850 census that John told me to look at has William H. Davis living in Marlborough,NY, age 17, born abt 1833.
     So, I see two different censuses for a William H. Davis in Marlborough,NY born only a year apart and I can see how either of these Williams could be mine.  My g-g-g-grandfather had a daughter named Adelia and the William who was born 'abt' 1832 lived with Adelia (his sister?).  The other William, born abt 1833 is listed with the Davis brothers whose Civil War records I found.  The last name is spelled wrong but I know that this is the correct family because William's brother's dates of birth on the census are the same as those in the Civil War records and the parents listed are the parents of William's brothers (from the Civil War records).
     Where was William in 1850?