The Homan Family

I am specifically searching for Gilbert Homan and his wife Sarah Downs.  Daniel Homan was their son 1815-1903, of Patchogue, Long Island, he married Elizabeth Gerard,1822-1870.  Her father, Mr Gerad, unknown given name, married Susannah Smith.  My search leads me to no end.

The other search that I am at a brick wall is with Mary J. Carman and Charles Preston, the parents of Mary Jane Preston-Homan-Warner.

Mary A Libby, according to census records has her listed as being born in the USA and other records have her born in Ireland. Both records have her listed married to William P Libby.  I have her mother on a marriage record listed as Mary L Libby as I hoped it would, but this is not sufficient evidence for the DAR proving that Richard Perkins to be my Patriot.

How may I come to a conclusion one way or the other?  It can be quite frustrating.  

I would appreciate any feed back.

Georgette L