I think the news of granny cooling the food with mouth is a bit extreme.
Pls bear in mind that your grand parents has more life experience than you.
While I agree is a bit unhygienic, I don't think is worth to kick up a fuss about it. As they did it in good intentions.
Maybe can just get another spoon for them to feed baby.. But then you might complain their food might have their saliva too.. Lol
By the way, the sharing of food during communue dinner helps built a up immunity among family members.
It has been a practice since ancient time, where family sit at a table and pass the food around to share.
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