Sorry maybe I didn't make myself clear in my other post. I know that the grownup Jessica we see in seasons 1 and 2 as Niki's reflection was her alternate personality or alter ego. What I meant was that that alter ego was based on Niki's real sister Jessica that died at age 11 (can check here a picture of Jessica's gravestone that Niki and DL visisted and a photo of both sisters that Linderman had:
So, I still believe it makes no sense now making Niki be Tracy and Barbara's triplet. Did the writers forget about Jessica??? I'm so confused!