Hay anak, yan talaga ang common problem kapag may formula milk na added sa breastmilk, sometimes ang baby's tummy gets upset sa combination kaya liquid ang poo, pero pag pure breastmilk lang okay naman. Since mas gusto ni baby ang formula para mas maraming dede, siguro yan ang comfort niya or mas mabilis kaya, but honestly, best na i-check mo with your pedia kung okay lang ba yung milk brand or kailangan switch ng formula, baka lactose intolerance or sensitivity lang sa particular brand. A few of us tried different formulas rin until we found the one na hindi makakasama sa baby's stomach, so don't worry hindi ka lang, pero huwag mag-experiment ng maraming brands at once kasi mas nakakalito lang ng baby's system. Kaya mo yan, mama!