Alma Margaret Reilly (June 16, 1900 – December 21, 1939), known professionally as Margaret Shelby, was an American stage and motion picture actress, daughter of actress Charlotte Shelby, older sister of silent film star Mary Miles Minter, and one of many public figures noted in the scandals which followed the murder of William Desmond Taylor in 1922.

By 1916, both sisters were quite famous and established a widely-publicized "hotel" for stray dogs on the ample grounds of their Santa Barbara, California home.

Her sister left the film industry in 1924,[3] and Margaret took small bit parts in sundry productions.

[citation needed] In March 1937, she eloped to Yuma, Arizona with Emmett J. Flynn, but this marriage was annulled two months later.

[5] On June 5, 1937 Shelby filed a lawsuit against her mother alleging financial mismanagement, claiming Charlotte had stolen $48,750 (roughly almost $2 million in 2007 inflation-adjusted terms) from a safety deposit box in a Los Angeles, California bank.