My 7yr old has suddenly developed some kind of insomnia. I wonder why
?
She's always been a great sleeper. However a month ago she stopped falling asleep happily at 7.30ish and now comes down at 8.30/9 most nights near tears saying she can't sleep. She says her sleeping muscle is broken 
She lies in her room, worrying. I've told her a hundred times that I don't mind when she falls asleep. Homeschool is odd, she's doing brilliantly, if she falls asleep late it isn't a problem for us. We've told her we understand how difficult the current situation is for her, she's reacting to missing school and her friends in a really normal way, etc etc.
Anyway, DP suggested maybe we push her bedtime a little later and make a new routine for her. I'm on board but just wondered what time is normal for a 7yr old.
She's perfectly happy to read solo in her room etc, but she's a very advanced reader and I'm not sure i want her reading her current faves just before bed when alone. Anything age suitable she reads in 10 mins, but if anyone does have any recommendations for a nice calming but loooong book which a bright 7 yr old could have as a special bedtime book I'll happily take that advice too! Or any Audible books etc?
Thanks in advance for any ideas