The following contains spoilers for The Sandman Season 1, now streaming on Netflix.
While Neil Gaiman's The Sandman takes place within the DC Universe, Gaiman avoided incorporating DC's more recognizable characters into the series after the first volume, Preludes and Nocturnes. One of the few exceptions is Lyta Hall, the mother of Dream's eventual successor Daniel Hall. Fittingly enough, Lyta's lineage was, at one time, tied to one of DC's most powerful heroes.
Originally, Hippolyta "Lyta" Trevor was the daughter of Earth-2's Wonder Woman. However, this origin would eventually prove too complicated for readers and comic book writers to understand. Following the events of Crisis on Infinite Earths, Lyta's backstory would be completely re-written, giving her a new origin that would (at least partially) carries over into Netflix's The Sandman.
In the alternate history of Earth-Two, Wonder Woman chose to retire from super heroics after World War II to marry her wartime sweetheart Steve Trevor, eventually giving birth to Lyta. Growing up, Lyta became friends with the children of other Justice Society of America members, becoming particularly close to Hector Hall, the son of Hawkman and Hawkgirl. After trying (and failing) to join the Justice Society, Lyta, Hector, and several of their childhood friends banded together to form a new superhero team. They called themselves Infinity Inc, with Lyta assuming the codename "Fury."
Throughout their adventures together, Lyta and Hector entered a romantic relationship that culminated in their engagement. Tragically, before he and Lyta could get married, Hector was possessed by the Silver Scarab, an Egyptian avatar of death, and placed under the control of Hath-Set, an old enemy of his parents. Forced to fight his friends and family, Hector ultimately lost his life, but not before learning that Lyta was pregnant with his child.
While Lyta's original status as Wonder Woman's daughter made her a unique figure within the DC Universe, it was also extremely difficult for new readers who weren't familiar with the complex history of Earth-Two to form a connection with her. Many of the writers and editors who worked within DC also shared the growing frustration with the interconnected nature of the DC Multiverse. As many within and outside the company argued that the complexity of the multiverse was driving readers away from DC Comics, the company's leadership decided to reboot the DC Universe by consolidating all the various "Earths" into a single, unified one.
Like many of the other multiversal characters who made their way into the "prime" DC Universe, Lyta got a new backstory. Instead of being the daughter of Wonder Woman, Lyta was now the daughter of Helena Kosmatos, a mentally-unstable Grecian rebel who served as an avatar of Tisiphone, one of the three Furies. Tisiphone fought alongside Wonder Woman's mother Hippolyta in World War II. While Lyta's tragic romance with Hector Hall remained unchanged, she was temporarily reunited with her fiancé when Hector's soul became lost within the Dreaming, allowing them to have a literal "dream wedding" in Infinity Inc. #51 (by Roy Thomas, Dan Thomas, Michael Blair, Lou Manna, Bob Downs, and Jean Simek).
In Netflix's otherwise-extremely faithful adaption of The Sandman, Lyta's origin story was changed again. She was re-imagined as an average human, leaving her with no connection to pre-existing DC characters. While this change may disappoint some fans, it allowed the series to retain its independence from the DC Extended Universe while introducing a semi-realistic storyline that both contrasts and complements the fantastical nature of Morpheus's quest to reclaim his throne.
Although there was nothing inherently wrong with Lyta's original backstory, her deep connection with a somewhat-obscure chapter of DC's history probably wouldn't resonate with younger DC fans who may not be familiar with its many intricacies. While there is a chance that a potential second season of The Sandman could establish a connection between Lyta and pre-existing DC characters, a lack of them would allow her to become a more original character.