It would be so helpful if Thomas b c 1849 had ever married. It looks as though the family headed by him in 1891 is likely to have been a mix of his children with Martha and hers from the Crampton marriage.
Rough suggested chronology here, building on what's been found:
1849 (Dec qtr): Thomas Reynard b Bradford (only a possible - 1891 census says 32 born Leeds)
1855: Martha Ann Hall born, Leeds, to Isaac and Sarah. Born 29 Apr; baptised 23 Sep, St Peter, Leeds.
1874: Martha Ann Hall (father: Isaac Hall, excavator) marries Joseph Crampton, St Peter, Leeds on 7 Feb
1875: Lily Crampton born, Leeds (with dad Joseph Crampton in 1891)
1878: Sarah Ann Crampton born, Bramley/Wortley (with Joseph Crampton in 1891)
1880: Ada Crampton born, Bramley/Wortley (with the Reynards in 1891)
1881: The Cramptons are in Wortley: Joseph, Martha Ann, Lily, Sarah Ann and baby Ada
1882: Margaret Hannah Reynard born, Leeds
1884: Florence Reynard born, Leeds
1887: Thomas Reynard born, Ashton (mmn Hall, per CheshireBMD)
1889: Albert Reynard born, Ashton (mmn Hall). Born 25 Feb, baptised St John, Hurst on 1 May.
1891: Thomas Reynard and Martha Ann living as though married in Ashton, with Ada and younger children.
1891: Joseph Crampton is in Leeds, still "married" but no wife. Lily and Sarah Ann are with him.
1892: Louie Reynard born, Ashton (mmn Hall). Born 11 May; baptised at St John, Hurst on 1 June.
1899: Elsie Reynard born, Mossley (mmn Hall).
1900 (Mar qtr): Joseph Crampton dies in Leeds aged 50.
1900 (Sep qtr): Thomas Reynard dies in Ashton aged 51.
1901: Martha Ann Crampton (a widow - father: Isaac Hall, navvy, decd) marries Thomas Harris, 31 Mar, St Michael's Westgate Common (Wakefield).
1902: Elsie Reynard dies aged 2, Wakefield. Buried Alverthorpe.
1904: Margaret Reynard marries, Alverthorpe.