Hi momsh! Usually kailangan mo itong i-transition gradually, hindi agad-agad, para hindi ma-upset ang tummy ng baby, try mixing the old formula with the new one for a few days, then slowly increase the ratio of Nido Jr until pure na siya. A few of us moms did this over about a week to 10 days, and it worked well para sa aming kids, pero if she gets constipated or may loose stools pa rin, better check with her pedia to make sure the new formula is right for her, okay? Praying it goes smooth sa inyo!