7 year old ds has always been great at going to sleep at night and until recently, probably around 4-5 weeks ago was usually asleep by 8pm. I usually read with him at bedtime and then he reads to himself for a bit before putting light out and then the fun starts - usually calls out "mummeeeeeeee, can't sleeeeeeep". We sometimes let him read for 5/10 more minutes and then say time to sleep but he then still calls out. I've spoken with him during the day and asked if anything is bothering him, he said no, and tbh he is his normal self, boisterous full of beans, happy. Seems tired at bedtime but this is happening every night and is exhausting. Have started thinking maybe he is just starting to need less sleep and therefore can go to bed a bit later but I do think 9.30pm is just too late for a 7 yr old's regular bedtime, especially on a school night. Help?!