Personally i dont think its unreasonable especially as shes up so early, mine have always been bound by boundaries incorporating a routine - so they know when bedtime is & not to push their luck - which they do try. Mine have done well at school & working as a TA [teaching assistant] especially in primary school i have seen the effects of late nights in pupils - it does effect their concentration - few have litterally fallen asleep in class, sleep deprivation also can causes behaviorial problems or moods with some children at school as occaisionally with my eldest it can cause her mood to increase if shes overtired, but then their are some children who it doesnt effect as with an person its individual thing how it effects , me i like me sleep lol.
They ALL try the 'everyone else but me' blackmail, but my response is the same what happens in other households is their business but what happens here is ours & stick to that. You know your own daughter Willow maybe comprimise slightly but then stick to it for an alternative if u wish or stick to your guns - give in then u ask for trouble because she could push u further on other issues effectively pushing all boundaries that teens are manic for doing, whether she likes it or not she needs to bound to the house rules as such as in life - there are many teens that dont & seem to think they can have it all their way without responsiblity, which i think is tountamount to our countries youth culture these days