The boy MUST die?"

Snape: So when the time comes, the boy must die? Dumbledore: Yes, He must die, Voldemort himself must do it. It is essential. cut to you in the forest with voldemort Voldemort: points his wand at you Avada Kedavra! you collapse and have pictures of voldemort flashing through your memories with snapes voice echoing Snape: You've kept him alive so he can die at the right moment? you've been raising him like a pig for slaughter