In case you aren't, In JMS's run on ASM he wrote a story called "Sin's Past" in which Peter Parker (not Spier-Man) is attacked by two masked people with powers. You eventually find out that they think he killed Gwen after getting her pregnant. Turns out these two super powered people are Sarah and Gabriel Stacy, Gwen Stacy's kids. Peter is confused, MJ tells him that back in the day Norman seduced Gwen and she got pregnant. Gwen went over to France for a while (that actually happened back in ASM in the 70s) and her twins came to term really quickly b/c they were Norman's and had super powers. She gave them up for adoption and came back and pretended it never happened. Shortly thereafter Norman kills her.
Then he went to Europe (during the time he was supposed to be dead, as was established in the Clone Saga) and found his kids and raised them to believe Peter Parker was their father and that he had killed their mother. He wanted them to kill Peter and then take the Goblin formula and become Goblins. Peter convinced Sarah Norman was lying to them, but Gabriel wouldn't listen and he took the Goblin formula. He became the Grey Goblin and he and Spidey fought. Sarah ended up stopping him. Last we saw of Gabriel he washed up on a shore somewhere and had lost his memory of being the goblin (as is common for people who had taken the Goblin formula).
then like i said before, he shows up in a tank being experimented on by Norman.