Yeah, unfortunately you have to catch them in the act if you plan to take action on it.
We've had a lot of family meetings about sleep hygiene; but then again, both affective disorders and insomnia are problems in our extended family, so this is one of those genetic things that requires lifestyle awareness for our DD in particular.
Another idea for you, though-- we definitely see sleep disturbances as one of the very first of the many warning signs that DD is struggling to keep a lid on her anxiety.
The other thing that we notice is that she has a LOT of trouble with sleep disturbances between November and March. Well, we live nearly at the 48th parallel, so this is also not a huge leap-- people who have SAD to one degree or another around here are more common than those who don't.
Combatting both of those things successfully has involved DAILY exercise (~1 hr) first thing in the morning-- and outdoors. In natural light. This provides the physical activity, the natural light from being outdoors, and it's early enough in the day that it doesn't trigger late-night wakefulness.
We also limit screen time within an hour of bedtime. This is one that a lot of people overlook, but it is the one that most physicians recommend trying first to manage insomnia.
Hopefully something in there is helpful. We've been battling this since DD was about three. She's never been a good sleeper, though.
