I think that Harry and Neville are twin brothers,reason I think this is because they were both born on the same day,and because Neville parents went crazy right? the big cover up is that Dumbledore keeps forcing false information like saying that his parents are still alive and are in a nut house so he wouldn't bother finding out the truth,and go looking for his real parents which are James and Lily Potter....

nevilles parents arent dead. they were tortured, until they went crazy, and they are in a hospital. and they were born on different days. neville on july 30, and harry on the 31.

hmm.. I really doubt this theory. Why shoul Dumbledore keep the truth from Harry and Neville, anayway? We know from the books that Neville's parent's were known as extraordinary good aurors who were tourchered to insanity.

I don't think Dumbledore had it all covered up and that every person who says they remember Neville's parents as very good peaople and very good which and wizard who fought against Voldemort and probably one of those who stood strongest against him, lied about all this. Do you really think Neville's parent's are a set-up? I would never believe that Dumbledore would do a thing like that to Neville. It would hurt him very much when he found out the truth.

there is no way that harry and neville are related. their are similarities yes, like their parents were both in the order, but there is no way that they are related.

How can two parents whose appearances we know are different obviously because they were all in the same picture be realted

it doesn't make any sense. I don't think Neville is related to Harry. He can;t be

If this theory were true, which it isn't why would Harry be sent to live with the Dursleys and not Neville's Grandma