I'm sort of stuck. I'm trying to follow a family tree back but I'm stumped as where to go next.

All I know is that Edward Bullen married Sarah Ann Firby November 24, 1897 at Aysgarth. I know nothing before this, nor do I know Edward's birth. I'm missing whether this Sarah Bullen was my great grandmother or my great-great grandmother as i don't know who had my Gramps, Sidney Bullen who was born in 1923. Sidney was raised by Gertrude Plant and her husband,she was a Firby as well but I'm not sure of the exact connections.