Okay, I noticed something in the books. Why can Harry see the thestrals in book 5? I thought he saw his mother die too?!

This is answered 의해 JK Rowling on her site:

Why could Harry see the Thestrals 'Order of the Phoenix'? Shouldn't he have been able to see them much earlier, because he saw his parents/Quirrell/Cedric die?

I’ve been asked this a lot. Harry didn’t see his parents die. He was in his cot at the time (he was just over a 년 old) and, as I say in ‘Philosopher’s Stone’, all he saw was a flash of green light. He didn’t see Quirrell’s death, either. Harry had passed out before Quirrell died and was only told about it 의해 Dumbledore in the last chapter.

He did, however, witness the murder of Cedric, and it is this that makes him able to see the Thestrals at last. Why couldn’t he see the Thestrals on his trip back to the train station? Well, I didn’t want to start a new mystery, which would not be resolved for a long time, at the very end of the fourth book. I decided, therefore, that until Harry is over the first shock, and really feels what death means (ie, when he fully appreciates that Cedric is gone forever and that he can never come back, which takes time, whatever age 당신 are) he would not be able to see the Thestrals. After two months away from school during which he has dwelled endlessly on his memories of the murder and had nightmares about it, the Thestrals have taken shape and form and he can see them quite clearly.

he didn't see his mother die, JK has said it herself he was sleeping when Voldemort went to his house, in the movie he is awake but really he didn't saw his mother die, and Cedric I haven't read the book in a while but I think he did saw him die, I'm not sure in that one

I think that he did see Cedric die it was like he saw his eyes bla bla bla. But yeah I think he did and your right why didnt he see them before.

yeah, exactly. He can't see them in the fourth book because he didn't realize what death is

Harry didn't quite understand what happened.

When Lily died Harry was in the crib, therefore not able to see what happened, but Cedric died in front of his eyes

He didn't actually see his parents die because he would have been really young and he didn't see Quirrel die because he had already passed out but then he can see them now in book number five because in book number four, when Harry was in the maze, Cedric was there too and they both used the portkey at the same time so they both travelled to the graveyard but Voldemort didn't want Cedric there, he only wanted Harry so Voldemort got Cedric killed right in front of Harry's eyes.

Harry could not see the thestrals until his fifth 년 because until that point, he did not truly appreciate the meaning of a death. When his parents were killed, he was in his 어린이 침대, 침대 and did not witness it, just the flash of green from Voldemort's spell. Since he never witnessed the death of Quirrell, it wasn't until he witnessed Cedric Diggory's death, and it had sunk in over the summer, that he could he see the thestrals.
OK!!SPELL_o_CHARM!

Harry was i 년 old. He's not goin to know what happened to his mother. Of course he should not have been able to see them. If 당신 are a i 년 old and your mother fell to the ground. are 당신 goin to know what happened. I would think not.

idk
but it might be since he was so little and his brain wasn't fully developed to take in the death

J.K did not think of thestrals until book 5 before that the carriages were pulled 의해 말

When his parents died, he was only a 년 old, nowhere near old enough to understand what death is. The flashback in Godric's Hollow in book 7 even states that he'd thought it was a game at the time. To see thestrals, a person needs to understand death as well as witness it.

As other people have explained, he'd passed out 의해 the time Quirrell died. Dumbledore had to explain to him what happened to Quirrell. He didn't witness it.

"Seeing death" is just a way of saying witnessing someone's death, it doesn't have to be literal seeing. Closing his eyes wouldn't matter. He still heard the incantation and knew what would happen, he heard Cedric's body fall and saw him dead afterwards.

Also, he didn't see the thestrals at the end of book 4 because Cedric's death and the whole experience hadn't sank in yet.

so, i think none of this can be a sware