A few questions I have...
There you go:
1) Did Benigna really kill those 5 children? If so, why? Was it as a revenge because they accidently caused Tomás's death? And what was the method she used to kill them?
2) What was the cause of Laura's death? Was it Simón's wish at the ending?
3) When Laura finally finds Simón in the basement, she finds him alive. But then she finds his mortal remains. How come she found him alive before she found him death? Perhaps what she saw before was his ghost?
4) When Carlos sees a door opening to him at the end, he smiles. Do you suppose it was the ghosts of Laura and Simón invisible sending him regards?
5) How did Simón found out that he was adopted and has HIV positive? Did he overhear when Benigna dropped by the orphanage and Laura said he didn't know he was adopted and that he had a disease.
«I was on the fire escape! I saw ya!»