Ay, ganito din ang nangyari sa anak ko around that age, at honestly nakita ko it was just a phase pero may patterns na nakatulong, a few of us moms realized na sometimes pag active sila buong araw, they're either tired or overwhelmed with choices, kaya we tried offering smaller, repeated meals instead of forcing big servings, at it helped na! Since super active pa rin ang sa'yo and walang signs ng sakit, I'd still suggest checking with the pedia just to rule out anything like worms or picky eating patterns na need addressing, pero in the meantime try adding nutrition sa mga gusto nya like mixing Milo with whole milk talaga (mas calories), or sneaking veggies into bread, kasi walang point mag-stress if she's thriving otherwise. Marami sa circle ko ang nagsabi din na when they hit school age, stress or changes (bagong klase, teacher, environment) can affect appetite, so check din kung may bagong nangyari sa buhay niya lately!