Dumbledore showed Harry the complete lost Prophecy. We learn that Neville could also have been the Chosen One. Dumbledore tells us this, and then insists it could only have been Harry. Why mention it then, in the first place?
Welcome to Loyal Trio, the approved fanlisting for the relationship between Neville Longbottom, Luna Lovegood and Ginny Weasley from the book/movie series Harry Potter.