What if Angela or Charlotte are still alive.

Reason 1. If Danny is Red John, maybe he would have spared his niece as he had nothing against her.

Reason. 2 What room did Patrick find them in, was it Angela's or Charlotte's.? Were they both in the same room at time of the murder? See we don't know that.

Reason 3. When Patrick opened the door that had the note on we never saw the bodies just the Red John smiley face, in blood, but whose?

Reason 4. Kristina had told Patrick that his daughter didn't suffer, she was asleep and didn't feel a thing.

Reason 5. It has been confirmed by Jane himself that  Red John likes to wake up his victims before he kills them, to see the terror on there faces. If Kristina was telling the truth then how come Red John did not wake Charlotte?

Reason 6 THERE DATE OF BIRTH AND DEATH IS NOT ON THERE GRAVESTONES.  WATCH THE LINK BELOW TO SEE THIS. http://www.youtube.com/watch?v=yYmsod3qlDM