I am very much afraid that the other granny in our family (ie our son in laws mum) is desperate to be the favourite granny and she’s played all sorts of sly little tricks, to try to ensure she’s the ‘best granny in the world’. I simply couldn't understand it, and I make sure that I never stoop to her level, although I have been tempted!
I have been hugely hurt by her manipulative behaviour but now I’ve learned to just go with the flow. Our grandchildren are now 8, 6, and 4, and they now seem to love seeing us but there was a definite time a few years ago when her insinuations were very negative and our oldest g’daughter in particular was very taken in by it.
I eventually reminded the granny, very calmly one afternoon after a particularly uncalled for comment by her, that it wasn’t a competition and that I had never said anything negative about her. I think she has taken notice, and I think things are improved BUT it was hugely hurtful while it lasted.
Incidentally, she is the paternal granny so I don’t think that it’s always to do with mothers/daughters or sons/mother but far more to do with individual personalities. ?.