Helene Costello (June 21, 1906 – January 26, 1957) was an American stage and film actress, most notably of the silent era.

[2] Costello first appeared on screen, opposite her father, in the 1909 film adaptation of Victor Hugo's Les Misérables.

[3] She would continue acting in films throughout the 1910s as a child actor and also worked in vaudeville and appeared in stage roles.

Shortly thereafter, both sisters signed contracts with Warner Bros.[5] Costello reached her peak of public popularity in the mid-1920s and earned a reported $3,000 a week.

[6] Although she had been appearing on screen since her early childhood, Costello was selected as a WAMPAS Baby Star in 1927, a promotional campaign sponsored by the Western Association of Motion Picture Advertisers in the United States, which honored thirteen young women each year whom they believed to be on the threshold of movie stardom.

[4] She was also beset with personal problems including illnesses, an addiction to drugs and alcohol, three divorces, a public custody battle with her third ex-husband and financial difficulties.

[17] In April 1948, Costello was forced to drop her suit due to financial troubles and Le Blanc was awarded temporary custody of Diedre.

[20] Her funeral was held on January 30, after which she was interred in an unmarked grave at Calvary Cemetery in East Los Angeles.