This is a (partial) timeline as I see it...
1869 - Henry Lomas born, son of Henry Lomas & Hannah Woodcock (reg Arthur Henry)
1874 - Gertrude Tomlinson born, daughter of Joseph Tomlinson & Susannah Fletcher
1875 - Walter Rawlins born, son of William Rawlins & Caroline Dufty
1898 - Walter Rawlins marries Mary Ann Flint
1901 - Gertrude Tomlinson marries Henry Lomas
1905 - Frances Lily Moore (Henry Lomas' future wife marries George Thomas Moore
1908 - William Lomas, Henry & Gertrude's youngest child born
1909 - Alice May Rawlins, Walter & Mary Ann's youngest child born
1911 - Henry & Gertrude (and family) living together in Small Heath
1911 - Walter & Mary Ann Rawlins (and family) living together in Balsall Heath
1914 - Mary Ann Rawlins (first wife of Walter) dies
1914 - 1916 Walter & Gertrude get together ?
1916 - Phyllis Edna Rawlins, Walter & Gertrude's eldest child born
1918 - Henry Lomas marries Frances Lily Moore
1919 - Lily Lomas, Henry & Frances' eldest child born
1926 - Frances Lily Lomas (Henry's wife) dies (reg Lily)
1935 - Walter & Gertrude living at Highgate Road
1939 - Henry Lomas living at Upper Trinity St with William (son) & Lily (daughter)
1947 - Walter Rawlins dies
1947 - Henry Lomas dies (reg Arthur Henry)
1949 - Gertrude Lomas (Rawlins) dies (reg Gertrude G)