User blog comment:Paul.rea/Teen Wolf News 030216/@comment-27038309-20160303052749/@comment-5182725-20160303172838

I think it is the same Theo. But Stiles did say near the beginning of the season that "That's not Theo." I think with their explanation of corrupting good to make pure evil, and that Theo was a failure because he was evil kind of makes me think he always had a dark side that he didn't show at school.

He was willing to take his sister's heart and watch her die for more power at such a young age, and maybe his parents just didn't want anything to do with him anymore. Since he was capable of killing his sister, maybe once he got older he killed his parents too. I have a feeling that none of these questions will be answered, and I don't care to be honest.