Long story short, dp does not speak or want anything to do with his ds since 2017. His DM can't see any fault in her dd, golden girl etc but lives overseas from her and only comes over to visit if there's a free holiday or even just to get her hair cut which was the case a few weeks back. Mil had a stay in hospital recently and dp went out of his way going in ambulance with her, visiting, sorting the cat out etc and golden girl did nothing except bark out orders from her iPad. Mil ds (their aunt) died recently and she asked my dp if he'd go with her to which he agreed but golden girl decided she wants to go so naturally, mil not bothered if dp goes or not now. It was mentioned over dinner today and she made mention that golden girls husband is also going. So I'm sitting there thinking well why can't they sit together an dp can sit with his DM? Got worked up as I was thinking of how much he had done for her when she was in hospital and she can't even return a kindness, so I called her out on it, "well I cant cut myself in half can I?" to which I responded "no but she always comes first doesn't she?". Should I have kept out of it or was I right to call her up on her blatant favouritism of her children?