Our pediatrician had us start offering water when he cleared DS for solids at 4 months. He still doesn't like it. We put some in a sippy for when he's eating, but don't force it on him as it isn't necessary at all.
You can start cereal anywhere between 4-6 months. DD was a little early so we waited until she was 5 months old. She doesn't care for it much but we offer a couple spoonfuls every night. They can start stage 1 foods at 6 months. Babies under a year old do not need supplemental water. They get everything they need from their formula and BM.
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Under one year you don't have to give babies water, however (I live in FL) my pediatrician recommended on a really hot day if he is outside or sweaty that I can give him a little bit of cool water to cool him down.
Re: When to start cereal and water
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