My 4 year old, CAN'T SLEEP/WON'T SLEEP/STAY IN BED! 7AM-10PM ARGHHH!!!

[peachcake]

As the subject says, my 4 year old daughter will not GO TO SLEEP AT NIGHT! She is up at 7/7:30am most mornings and is as grumpy as f**k at tea time, has an excellent bedtime routine, bath, story etc etc, all ending in lights out at 8pm but still refuses to settle.
She is in and out of bed, asking questions, singing, looking at books, chatting to her brother (they share a room & bunkbeds unfortunately for him) she does everything but bloody fall asleep!
We have tried ignoring, putting straight back to bed, earlier bed times, later bedtimes all to no avail.
My poor son now 10 yrs would like a later bedtime but her behavior is even worse if she is put to bed alone with screams and shouts of "I'm scared on my own" even when hubby or I are sat in the next room to reassure her.
I know it's not fair on my son, using him to make our lives easier but don't know what else to try...
Didn't mention we have tried sticker charts and rewards, these were successful for a week or so then she was demanding a end of week present after each "good" night!! Crafty madam, she told us she didn't want a star chart if she had to wait for seven stickers :o
Has anyone got any ideas, advice or been in a simular situation? We just don't know what else to do, she starts school this coming Monday but I don't think that will solve the problem, as I have well and truly worn her out over the hols but it hasn't tired her out, I'm worried she's going to be a grumpy little sh*t at school and everyone will dislike her as we do sometimes!!! She is super volatile and has no tolerance what-so-ever!!!
HELP!!!!!!!

I have one of these. She's 6 and I am at my wits end too.

Like you we have tried everything, reward charts, ignoring, praise, sanctions, bloody everything, and NOTHING has worked ever. I don't belive this is a parentng problem, we have3 other dc between us, and none of them were any trouble at bedtime. I just think some dc are born this way

I also think she is an owl, and she is at her best in the evening and 1/2 asleep in the morning. have come to the conclusion that she has a very small window of falling asleep time, and if we miss it, then she gets overtired and hyper. However this "time" seems to be at a completely different time every night.

Glad we're not alone I do wonder if it's behavioral with her as she is the youngest and most demanding and stubborn of the four!! Although they were all the youngest once and were at 4 years old mostly (I have big age gaps between my kids)
Even if it is my crappy parenting, I would love some advice to remedy this situation...

Well.....if she is sleeping 10pm - 7am that is 9 hours and, to be honest, that's all I can expect from my 4 year old. I think it's all a myth that they sleep longer. He went to sleep tonight at 9.45pm and I expect him up before 7, always is.

So if your son wants a later bedtime then I would say later it is, for both of them.

Either later bedtime for both or just close (and lock if necessary) the door and ignore her til she falls asleep. She might be loving all the attention iyswim.

Thank you for your suggestions! She started school yesterday so I don't want to be too harsh with the changes so I think your suggestion of later bedtimes for both is a brilliant one:) So simple but I didn't think of it, as long as she isn't too tired in the morning. Can't see my son liking it too much but oh well, he'll have to accept that this is the way we are going (at least for now!)
Thanks again! xxx