I realise you are after more information before the marriage of Frances Marion Bown nee Baker, but in the process of searching on Ancestry I came across the baptism of her daughter Constance Frances Marion Bown which gives her date of birth as 29th August 1890 (GRO ref Q4 1890 Edmonton district, mmn Baker). She was baptised at Christ Church West Green Haringey on 1st February 1891. The family were living at 7 Beaufort Road West Green and Willie's occupation was given as clerk.