Milk for 1year old

Any milk n ok kay baby.. 1yr old n po sya.. Yung una kc lactum 1 to 3 years old milk nya hiyang s knya kc ambigat nya kaso hirap sya magpoop duon.. Switch nmin sa nido ok nmn poop kaso nmayat at gumaan 1week plng syanagninido.. Ano po kaya mgndang gatas.. Pag binalik kc nmin s lactum mahirapan n nmn sya mgpoop any suggestion po mommy