Mrs Lewthwaite used to be Mrs Blackett's nurse, and that of the Amazons when they were young (SA24) & (PM23). She is the mother of the local policeman Sammy Lewthwaite and odd-jobs-man Billy Lewthwaite. She and Billy, and possibly Sammy, live in a cottage not far from Beckfoot (Cook (Mrs Braithwaite) runs there to get her son Billy Lewthwaite to drive Rattletrap; PM25). Mrs Lewthwaite often "has a crack" (a conversation) with Mrs Braithwaite (PM23) & (PM26). Jacky calls her Old Mother Lewthwaite (PM29).