I don't think iabu in the least really. But i am a but at the reaction of everyone else.
DP, DS and i went out for lunch with PIL. Fil ordered a bottle of beer with his food. DS, who has an obsession with bottles since he no longer has one, was in the highchair sat between me and fil. Ds kept gesturing towards the bottle, like he does with any bottles, so i got up to get his cup from his bag, i heard fil saying look, look, turned round and he was giving ds a drink of his beer. I was shocked, and said, 'don't you dare, what are you thinking?' both dps parents were laughing loudly, dp was just shaking his head AT ME but i was so angry.
Later on in the day, i was outside with ds playing and they were talking about the drink, mil brought up that i was only bothered because it wasn't my parents. This is so not true, if anything i would have reacted worse with my own parents.
PIL like a drink, and that is their thing, it doesn't bother me what they want to do, but it does bother me when they want to feed my ds beer.
Nothing else was said about it from me, only at the lunch. So i didn't go ott or fall out with anyone. But dp things i am being daft, and his parents think i am mental and his mum thinks i should say sorry because i embarrassed fil and ruined his day.