The Cowboy Millionaire is a 1909 American silent short western directed by Francis Boggs and Otis Turner.
 The film stars Tom Mix, Mac Barnes and William Garwood.
 It was the debut film of Mix and Garwood, as well as William Stowell.
The League of the Future is a 1916 American silent short directed by Edward J. Le Saint.
 Starring William Garwood in the lead role.
 It is the fifth in the five series "Lord John's Journal".
The Human Side is a 1934 American drama film directed by Edward Buzzell and written by Edward Buzzell, Frank Craven and Ernest Pascal.
 The film stars Adolphe Menjou, Doris Kenyon, Charlotte Henry, Reginald Owen, Joseph Cawthorn and Betty Lawford.
 The film was released on September 1, 1934, by Universal Pictures.
You Can't Always Tell is a 1915 American silent short film directed by and starring William Garwood in the lead role with Violet Mersereau.
 It is one of several short films that Garwood and Mersereau starred in together and Garwood directed.
The Decoy is a 1916 American black and white silent short drama film directed by William Garwood, and starring William Garwood, Edward Brady, Lois Wilson, Wadsworth Harris and Frank MacQuarrie.
 The film premiered on October 19, 1916.
 The film is said to be a story of "revenge and intrigue" with its scenes set in Paris according to the Moving Picture Exhibitors' Association writing about the film in 1916.
He Wrote a Book is a 1916 American silent short comedy directed by and starring William Garwood and Edward Brady.
 Lois Wilson also starred.
Transient Lady is a 1935 American drama film directed by Edward Buzzell and written by Edward Buzzell, Arthur Caesar and Harvey F. Thew.
 The film stars Gene Raymond, Henry Hull, Frances Drake, June Clayworth, Clark Williams and Edward Ellis.
 The film was released on March 4, 1935, by Universal Pictures.
Buzzell was born in Brooklyn.
 He appeared in vaudeville and on Broadway, and was hired to star in the 1929 film version of George M. Cohan's "Little Johnny Jones" with Alice Day.
 Buzzell appeared in a few Vitaphone shorts, and the two-strip Technicolor short "The Devil's Cabaret" (1930) as Satan's assistant.
 He wrote screenplays in the early 1930s and later produced the popular "The Milton Berle Show" which premiered on television in 1948.
William Davis Garwood, Jr. (April 28, 1884 – December 28, 1950) was an American stage and film actor and director of the early silent film era in the 1910s.
Arthur's Desperate Resolve is a 1916 American silent short comedy directed by and starring William Garwood and Edward Brady.
 Lois Wilson and Alfred Allen

Question: Did William Garwood and Edward Buzzell both act in films
Answer: yes