What I can glean from the search results for the 1921 census is that William, Gladys and Arthur are living at 121 Deakins Road. William's birthplace is listed as Rhiwlas, Carnarvonshire (mentioned previously) and his occupation is listed as Fitter Labour.
Deakins Road is in the Hay Mills area of Birmingham but in 1921 came under the Kings Norton district.
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