Kindred was revealed to be Harry Osborn a little earlier in Nick Spencer's Amazing Spider-Man run, a bizarre twist when the character has been a close friend of Peter Parker's since his resurrection during the events of "One More Day." It was explained that the former Green Goblin had likely gone off the deep end again, but there's more to the story than meets the eye.
In today's issue #66, the "cleansed" Norman Osborn frees his son. However, after Harry talks about fighting his way through hell to finally earn his father's love, it's revealed that it's all just a ruse and he proceeds to savagely beat Norman.
In an epilogue, Carlie Cooper is revealed to be imprisoned, but there's someone else in her cell: it's Harry Osborn!
What does this mean? Well, the theories that the "Brand New Day" Harry was some sort of doppelganger created by Mephisto may, in fact, be correct. It seems Harry's soul remained trapped in hell, and that's why he's only just now managed to return to Earth to wreak havoc on Spider-Man's life.
When Harry died, it was as the Green Goblin. He saved Peter's life as his final act, but was still one of the wall-crawler's most twisted enemies. However, in order to use the character in that reboot of Amazing Spider-Man, Marvel Comics explained that Harry never died and actually just spent some time in Europe recovering from his drug addiction. Peter was oddly accepting of that, and it's clear now that Spencer has a lot of explaining to do as we near issue #900.
Peter's soul is somehow caught up in this, and there being two Harry Osborns could be more complicated than we think. Oh, and just to further shake things up, Amazing Spider-Man #66 also revealed that Betty Brant is pregnant!