Question: Did Stephen Spender and Mary Stewart write about the same themes?

Context paragraphs:
Auden Group: The Auden Group or the Auden Generation is a group of British and Irish writers active in the 1930s that included W. H. Auden, Louis MacNeice, Cecil Day-Lewis, Stephen Spender, Christopher Isherwood, and sometimes Edward Upward and Rex Warner.  They were sometimes called simply the Thirties poets (see "References").

Mary Stewart's Merlin Trilogy: Mary Stewart's Merlin Trilogy refers to the first three of Mary Stewart's quintet of Arthurian novels.  It consists of:

The Temple (novel): The Temple is a semi-autobiographical novel written by Stephen Spender, sometimes labelled a Bildungsroman because of its explorations of youth and first love.  It was written after Spender spent his summer vacation in Germany in 1929 and recounts his experiences there.  It was not completed until the early 1930s (after Spender had failed his finals at Oxford University in 1930 and moved to Hamburg).  Because of its frank depictions of homosexuality, it was not published in the UK until 1988.

Matthew Spender: Matthew Spender (born 1945) is an English sculptor.  He is the author of "From a High Place: A Life of Arshile Gorky" (1999), a biography of his father-in-law, the artist Arshile Gorky, and "A House in St John's Wood" (2015), about his father, the poet Stephen Spender.

Natasha Spender: Natasha Spender, Lady Spender (18 April 1919 – 21 October 2010) was an English pianist and author.  She was the second wife of the writer Sir Stephen Spender.

Twenty Sonnets to Mary Stewart: Twenty Sonnets to Mary Stewart (Russian: Двадцать сонетов к Марии Стюарт ) is a cycle of sonnets Brodsky, written in 1974, published for the first time in Russian Literature Triquarterly, 1975, №11 and in 1977 in the book "Part of Speech".  According to the classical structure, "Twenty Sonnets to Mary Stewart" consists of 20 verses and 14 lines each, written in iambic pentameter.  Brodsky extends the concept of a sonnet - both formally and stylistically.  He alternates or mixes French, Italian and English types of sonnets, and uses unusual for sonnets rhyme schemes, and quite atypical (for example, in the last stanza) a breakdown of the sonnet into parts.

Philip Spender: Philip Spender (1943- ) is a prominent public-sector fundraiser who has worked with Index on Censorship, the Writers and Scholars Educational Trust, and OneWorld Online.  He is the son of the painter Nancy Spender and the explorer Michael Spender, a nephew of the poet Stephen Spender, and a trustee of the Stephen Spender Memorial Trust.

Stephen Spender: Sir Stephen Harold Spender CBE (28 February 1909 – 16 July 1995) was an English poet, novelist, and essayist who concentrated on themes of social injustice and the class struggle in his work.  He was appointed Poet Laureate Consultant in Poetry to the United States Library of Congress in 1965.

Mary Stewart (novelist): Mary, Lady Stewart, "née" Mary Florence Elinor Rainbow (17 September 1916 – 9 May 2014), was a British novelist who developed the romantic mystery genre, featuring smart, adventurous heroines who could hold their own in dangerous situations.  She also wrote children's books and poetry, but may be best known for her Merlin series, which straddles the boundary between the historical novel and fantasy.

Encounter (magazine): Encounter was a literary magazine, founded in 1953 by poet Stephen Spender and journalist Irving Kristol.  The magazine ceased publication in 1991.  Published in the United Kingdom, it was a largely Anglo-American intellectual and cultural journal, originally associated with the anti-Stalinist left.  The magazine received covert funding from the Central Intelligence Agency, after the CIA and MI6 discussed the founding of an "Anglo-American left-of-centre publication" intended to counter the idea of cold war neutralism.  The magazine was rarely critical of American foreign policy, but beyond this editors had considerable publishing freedom.

Supporting paragraphs: Stephen Spender Mary Stewart (novelist)
Answer: no