Benjamin Wade could be her brother. There is a baptism record for a Benjamin Wade on 4 Feb 1794 at St. Mary, Barnsley son of Joseph and Hannah Wade, born on 23 Jan 1794. This ties in with a baptism for Esther Wade, daughter of Joseph & Hannah, on 3 April 1795 at Ossett, Dewsbury.
Also ties in with your mentioning that Esther had a son Joseph - presumably named after his maternal grandfather.
What Vital Records site are you looking at which mentions Thomas & Mary Ward?
Pheno