Actress Ilene Kristen originated and last played the role, that was created and introduced by Claire Labine and Paul Avila Mayer and first appeared in the pilot episode first broadcast July 7, 1975.

Delia is the catalyst for many of the show's story lines and remains a central component of the series throughout its run.

In 2013, Kristen would reprise the role of Delia on the sole surviving ABC drama, General Hospital where she is revealed to be the mother of the treacherous Ava Jerome (Maura West).

After failing to impress as One Life to Live's Georgina Whitman, Kristen was left unemployed allowing for her to return to Ryan's Hope.

In early October 2013, several reports surfaced and claimed that Kristen would reprise the role of Delia on the remaining ABC Daytime soap, General Hospital.

[15][16][17] In May 2014, newcomer Michelle Stafford revealed that she had taped scenes opposite Kristen indicating that the actress would reprise her role of Delia.

Michael Denis said Kristen displayed a specific kind of "manic verve" as well as "troubled" and "erratic."

Her father ends up in a mental institution and her mother works herself into an early grave leaving Delia in the care of her older brother, Bob.

Delia becomes close to the Ryan family when the matriarch, Maeve (Helen Gallagher) shows her kindness and gives her food.

However, when Delia begins an affair with Dr. Roger Coleridge (Ron Hale), Jill's brother, Frank divorces her in February 1977.

During the marriage, Delia resorts to extremes to keep Patrick's attention including faking a miscarriage and a mental breakdowns.

Delia later opens her own restaurant, The Crystal Palace and begins dating Ryan family cousin, Barry (Richard Backus).

When Delia finds out Barry has been cheating on her, she runs him over and frames her former sister-in-law, Faith Coleridge (Karen Morris-Gowdy) for the crime.

Due to lack of finances, Delia loses her business to mob boss, Joe Novak (Roscoe Born); however she is forced to shut The Palace down in 1982.

In actuality, Frank (Geoff Pierson) sets up the job with the help of Rae Woodard so he can get custody of Little John.

Delia resurfaces on June 15, 1984 when she marries wealthy oilman Matthew Crane (Harve Presnell).

The marriage quickly falls apart due to Delia's affair with Steve Latham (Franc Luz).

Delia sets her sights on Roger once again and does her best to win his affections from his wife, Maggie Shelby (Cali Timmins).

[24][25] Delia was introduced on General Hospital in October 2013 when she is visited by Sam Morgan (Kelly Monaco) and Silas Clay (Michael Easton) and forced to admit that she is the biological mother of Ava Jerome (Maura West) from an affair with late mobster, Victor Jerome (Jack Axelrod).

To protect her daughter, Delia tries to steal information implicating Sonny in another murder but is caught and sent back to New York.

Ronni Ashcroft who praised Kristen for her portrayal said, "it's a wonder she's able to pull off Delia's bitchiness so convincingly" because the two were exact opposites of one another.

Because the actresses were so different, "it's hard to imagine Delia reverting into the character that Ilene made her originally," said Hirsch.

[22] Seli Graves agreed with Kristen's assessment in 1988 and said the character "resisted anyone else's efforts to bring out the unique qualities" of Delia.

[7] In 2023, Michael Fairman from Michael Fairman TV wrote that fans "will always remember" Kristen's portrayal of Delia, commenting that the character "definitely stirred the pot in the Ryan family and was responsible for many machinations and issues that she caused the clan; all in her efforts to find love.