Speculatively this is left to right, Ada Boydell 1904-1975, father James Boydell 1868-1930,(Lilian Boydell's uncle) with wife Henrietta Boydell, née Grimshaw 1871 -1928, Dorothy Boydell 1909-2003 and Cyril Boydell, 1901-1972. If you can confirm or correct, please contact me.