the amount on the tin is just a rough gauge, because it also depends on how many times you are feeding per day. if u see the pd the doc will tell u that if your baby is gaining weight, peeing and pooing well it is totally fine.
at 3 months old, some of my friend's kid is drinking 350ml to 500ml total per day (they grew up fine and healthy, 3yo+ now) while they should be drinking 700ml/800ml according to the formula that they use to calculate how much they should drink, weight multiply by 150. eg if weight is 5kg multiply by 150, baby should be drinking 750ml. but this is just a reference only also. most can't reach the amount and is totally fine.
my kid should be drinking 900+ml according to this formula but only drinks 700 - 800ml. during bad times 500+ml. same thing pd will always say that if your baby looks fine, weight gaining, pee and poo normal then it's ok.
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