Why does harry only see Thestral in the 5th Film? he saw his mum die, why did he only see them after Cedric died?

I am guessing that he actually didn't see his mum die. We know from Deathly Hallows that he was in the crib at the time, so perhaps he was not watching his mother. Or, if he did see her, it could be that he was too young to remember it, so seeing death doesn't apply. Just theorizing.

I agree, he probably only heard his mum die. But didn't he see Quirrel die in PS? What about that?
And Cedric's death takes place at the end of GoF so Harry should be able to see the Thestrals already when they pull the carriages back to the station in GoF but he only can see them from the beginning of OotP on. I think JKR herself said in an interview that she made a mistake there. She didn't want to introduce the Thestrals in GoF.

I'm guessing it takes time for the effect to be stored in.
Maybe it only takes effect once he truly accepts the person is gone, and... Well, dead.
It is known, of course, that some people just won't accept their loved ones death.
And we know that harry did consider Cedric a friend.
Some people will deny it till their own bitter end and will try to bring their loved from the grave even.

Yeah, JK has said that you need to be able to process and comprehend it. That's why he didn't see thestrals right after Cedric's death on his way to the train in the carriage. Whether or not he saw his mother die, I don't know. But it would've been an incredibly difficult feat for a baby to understand death.

it's one of many inconsistencies in the books, and JK did admit to the error.
as a baby, he probably wouldn't have registered that his mum had been killed. I'm not so sure about the Quirrel case.

But in PS the book Harry faints before Quirrel actually dies...if I remember properly!

Doesn't he black out while he's still screaming?

Yeah, ok good arguments, but Harry kept seeing the green flash and if he sees the flash, he obviously sees his mother at the same time

JK explained. It's not just seeing, its comprehension as well. At the time Harry did not understand what was happening. Also, we don't know where he was in relation. He may have been in the cot and blocked from view so...

But with Cedric, he was there. He saw it and understood what had just happened. That made the difference.

Oh! An admin replied to my thread

Ok, Thanks Dainsie!

JKR also said that you have to dwell on it a bit, to really understand the finality and reality of death.
That's why Harry didn't even see the Thestrals on the way back to the Hogwarts Express at the end of GoF. He was still in shock, and a bit in denial.
You may have heard of the 7 (some say just 5 )stages of grief: Shock, Denial, Grief, Guilt, Anger, Depression, and Acceptance:

You don't see the thestrals until you go through all of them, and though they sometimes skip or jump, it always ends with acceptance.

I agree with everyone else....that he had to accept it before he could see them.

Ya I agree With b stewart..

I agree you need it to sink in a bit. But I also don't think he saw his mother die as he was in the crib at the time (as to him seeing the flash - that spell destroyed the whole house so I'm thinking big bloodly flash!). Also it was said that Voldemort had 'left Quirrel to die' so I'm thinking he wasn't dead until after Harry had lost conciousness/been removed from the room.

A good question though.

I agree w/ the first post, and to the Quirrel thing, i think that b/c it was voldie, partially, that it didn't count.

i still don't get that he saw a lot of things die! i gues Rowling had a good idea about what she was talking about...