I am very straightforward de, my mil used to do it too. She wanted to feed my children some biscuits so I told her it is too big; she might want to half it first before giving to her. She bite it into half and give the other to my girl when she is coughing. I will tell her nicely but if she give me excuse like, "I am her Grandmother why cannot share or my saliva got poison is it?" I will stare at her and tell her out loud "Yes". I rather being the bad guy than putting my kids at risk.
I found out being nice don't work well with some old people! I have tried talking nicely or jokingly, sharing news report, let PD/expert do talk but none work. Only Honesty will do the trick.
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