This post contains details from the season finale of FoxsAlert: Missing Persons Unit.
But if he wasnt their son, how did he pass a DNA test?
And how did he know so much about their family and their past?

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But before they can celebrate, Keith is taken again.
What Keith wanted was the jot down of family he never had.
I always imagined that he was someone who was not a villain, but a troubled young man.

He was in a situation with his biological mother that was terrible.
How did you craft these final two episodes to bring Keiths mystery to a close?
What Keith wanted was the key in of family he never had.
I always imagined that he was someone who was not a villain, but a troubled young man.
He was in a situation with his biological mother that was terrible.
He started to fantasize about it.
What if that was him?
What if he could be in that position?
Then they watched him die.
There has to be some lasting trauma there.
It is the most joyous thing any parents could imagine the return of their missing child.
The parents are suddenly confronted with [questions].
Theyve come to love this person.
Hes a kind, decent, sweet young man who we have come to embrace.
I think that in the month before Keith dies, they are genuinely torn.
It is an interesting question, to wonder, if he hadnt died, what would they have done?
Would they have left him?
Would they have found a way in their hearts to understand and empathize with this troubled young man?
EISENDRATH:Well, a couple of things.
Her initial explanation when asked why she didnt come forward, I thought was very compelling.
Sidney was saying, I thought you would reject me.
So I think that they understand what motivated her to not say anything.
That goes alongside the endless numbers of missing persons cases.
I love Kemi and exploring more of who she is.
We just touched on how she became the person she is and her relationship with her dad.
Im confident we have a lot of incredibly interesting ground to cover.
DEADLINE: You mentioned this procedural being a little different than previous series youve worked on.
What did you take away from this season that will change how you implement things going forward?
That definitely turned out to be true.
Then much more complicated psychodramas and theyre all missing persons cases.
Not one episode would be similar to the next, and that is what I think is very exciting.