"DEACON WILLIAM FISKE, OF WENHAM.
William Jr., ... was married to Sarah Kilham, ... and by her had the following fourteen children, the record of whose names and births was found among the private papers of his grandson, William Fiske, Sen., of Amherst. ...
Elizabeth, born Dec. 12, 1684; married Eliezer Foster, 1704."
The author goes on to say that William Fiske's children are all mentioned in his will (except for one who had died), but "no clue is given to the families intermarried, none of them being mentioned by name." It isn't clear if this means that Elizabeth was mentioned just by first name, or as Elizabeth Foster, which would support the supposition that it was this Elizabeth Fiske who married Eleazor Foster.