I think you answered your own question there - she has an adorable chubby fact - I certainly wouldn't be worried about her not eating enough. My DD eats the same way - lots up to lunch and then sparsely for rest of day - try making her an omelette in the mornings for breakfast so you can put grated veggies in that, or putting the fruit in with her weetbix and then veggie sticks of something for morning tea if not enough veggies at night as that's what we've had to do- my bubs skinny though and has lost weight from a nasty tummy bug so have been thinking of putting some toddler formula in with her milk since no breast milk from me but YES, your breastmilk has lots of nutrients in it for your bub, much more than something sugary and artificial like Milo.