There's a William Arthur Plumb b January 1923 who died in 1984 - address Whitley Bay, Tyne & Wear, but death looks to have been registered in Bolton. So if he's the right one, they divorced, or she never married Mr Brown
Fairly sure now he's correct - matching birth in 1923 with mmn Seeley. Marriage in 1922 of Henry C Plumb to Lily Seeley - matches father on the marriage registration