I don't know where she got her information from, but that is NOT true - breastmilk is beneficial to LO even as a toddler, or even up to 5-7 years old.
It's probably better if you could find more recent information (I reckon it could be from the past generation where they were brainwashed that formula is best, my mum took medication to stop breastmilk production because media at that time was promoting formula and saying breastmilk is bad).
Also, breastmilk has many awesome qualities other than just as key nutrient source until 1 year old - it can also help with infections because of its antibodies, be used as milk bath for sensitive/irritated skin, made into keepsakes and a lot of other useful purposes too!
In fact, breastmilk has the quality to change itself as per your baby's needs - hence you can see it being thicker sometimes or even blue-ish with antibodies when LO is sick :)
Please don't throw away your precious milk! If you have too much extra, you can do milk baths with them or donate them to other mums :)
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