The only one I can see in Hampstead Road in 1955/56 is Herbert B White at number 189. With two Ferrimans, no other Whites, and no Eileen.
Not sure what happened with that address later!
Could he be the Herbert B White who married Gladys E Turley in Pancras in June qtr 1939?
Probably that is Gladys Emma Turley born in Pancras in 1916.
Looking for them in the free index to the 1939 Register, I think they are living in Pancras
Herbert B White, born 1909
Gladys E White, born 1916
The free index on findmypast gives address in Hampstead Road.