Just a few of my thoughts following what you've said:
She doesn't seem abnormally tired though. She often seems more tired after a 7-7 night!
Do you ever feel more tired after a long lie in (do you remember what a lie in feels like??)?
I tend to keep going through the week or for several weeks, appearing not tired but in reality missing some sleep pretty much every night. If I do get a lie in (even after a disturbed night) I *always* feel more tired when I wake, dopey. Ii complain about needing a lie in when I am really exhausted but then complain after the lie in that I have over slept. I think the reality is that I do miss out of sleep pretty much every night but appear energised enough, then when I catch up on my sleep I appear more sleepy but my body needed it.
Whilst younger LOs seem to show their tiredness a bit differently I think at 3yo they can feel just as dopey after a longer sleep, my DS did/does if he randomly falls asleep in the car, he appears more tired and dopey (and grumpy) than he would if he just kept on going.
She seems to go through phases of sleeping a lot and eating a little or eating a lot and sleeping a little. At the moment she is eating everything she is given and a few extra yogurts too!! So I'm wondering if you guys have ever noticed this.. have you heard of children going through a phase of eating in favour of sleeping?
No never heard of this but clearly it can happen as you've observed it with your LO
but...
Even last week she was waking at 5am saying she was hungry and asking for a yogurt.
I have had this during growth spurts, well not at 5am because mine follows his timer-light rules so keeps quiet until 7am but at 7am rather than read his book he will come and say right away he is hungry and needs a banana. Usually he wouldn't have anything for at least 30 mins after WU then he has milk followed by breakfast so for him to tell me right away he needs food is a clear growth spurt. It makes no difference if he has eaten a lot the day before, he just needs food immediately.
Maybe I should mention she's quite thin. Within the normal range but lower percentile than average weight.
Mine is also petite, between 4ht and 25th centile on weight, 50th for height so he looks very slim - but has a very good appetite and will still eat the fridge empty during a growth spurt! Sounds like your DD is the same
So I don't really know what to increase. Maybe a bigger bowl of dinner at 4.
I always let DS guide me on how much and when. Most kids eat more in the morning and lunch time rather than dinner time but you can increase anywhere she seems to be hungry for an extra portion, or add in the option of a piece of fruit/bread/cheese if she is still hungry after a meal. I didn't see any snack times on your example, pretty much all the kids I know had a mid morning (around 10.30/11am) and mid afternoon (around 2.30/3pm)snack as well as their 3 main meals and possibly supper. If she appears full at meals times maybe she can fit in a snack a couple of hours later and still have a good appetite for her next meal? If there is any question over waking early because she is hungry I'd probably offer more or at the additional times.
i see she gets a good couple of portions of fish and meat, does she also get some fat? Is the yoghurt full fat for instance? This could make a difference. It's ok to give kids this age reduced fat versions but again if there is a question of hunger it's one of the things I'd probably switch to full fat to make it higher calorie. Mine still has full fat milk.
Not sure anything here will help, maybe, hope so.