@Nata she loves fruit
Girl I got you, as a former nanny I know so many tricks; Add a splash of fruit-infused water (lemon, strawberry, cucumber, or mint). Get those sugar-free water flavor drops (just a tiny bit can make a difference). Let her “design her own water recipe.” (Look up the tag watertok on tiktok. It’s shocking but a it’s step into having them stay hydrated. Obviously try a tamer version of what they do tho) Also! This may sound silly but it works: A bottle with cool designs, a flip straw, or a chug top can make a HUGE difference. Let her decorate it with stickers, her name, doodles, etc. Or one with lines for time markers (“Drink to here by 10AM”).
Do they like fruit ?? You can add slices in the water if your comfortable with that and get cute fun like drinking cups etc