Did you get the birth details from the 1871 census for Wardour St in Westminster? I couldn't find anything for them in Familysearch apart from some member submissions which presumably derived from the same source. In the 1881 census I could only find Reuben Douglas Perkins, grandson, 16 and Eliza L. Perkins, granddaughter aged 10 - they are with Thomas W. Corlett and his wife Eleanor.