WARNING! This article contains SPOILERS for That ’90s Show part 3!While That 90s Show parts 2 and 3 were able to cleverly avoid bringing back Topher Graces Eric Forman, the characters absence is becoming more difficult to justify. That 90s Shows cast of characters is centered around Leia Forman (Callie Haverda), the teenage daughter of That 70s Shows Eric Forman and Donna Pinciotti (Laura Prepon), as she spends her summer vacations in Point Place with her grandparents, Kitty (Debra Jo Rupp) and Red Forman (Kurtwood Smith). With Red and Kitty taking over as Leias guardians in the sitcom, Donna and Eric have taken the backseat in the sequel series.
https://screenrant.com/that-90s-show-part-3-eric-forman-ignore-difficult/