The dummy thing isn't just gross it's potentially dangerous. Licking/sucking it won't ensure there's no small bits she's missed that baby could suck and then choke on, and if she ever gets cold sores or has certain other chronic conditions or is on certain meds that is a whole other scenario!
Blanking you, pointedly address this it's ridiculously rude and completely unacceptable, pull her up on it every time
Do not use her for childcare she won't do anything you ask her to and clearly can't be trusted to listen to new/current childcare advice
Putting his name down for school?! If it's a state school she's full of it, that's not how it works if it's private Wtf!! I'd have gone apeshit! Tell her this is completely out of order! (And wtf were the school thinking?!)
Time for a sit down chat with partner he HAS to back you up, point out to him every time she does something batshit - then he can't claim he "hasn't noticed" but as is often the case you likely have a "dp" problem. Ask him why he refuses to acknowledge her actions as weird, because they bloody are!
My now ex mil is/was lovely however my mother was a nightmare! I also had the dummy, jealousy over mil having time with dd, trying to arrange a christening for dd when we weren't planning on christening her...
Just bonkers!
And even though it was my mum I got really frustrated with then dh not backing me up as it left me not wanting to leave dd with them when it would have meant I got a break because I couldn't trust him to step in when she did something nuts like trying to give dd bloody honey at 4 months!
You do REALLY need to get over the "awkward" thing, not just because of mil.
There will be many occasions you need to step in or speak to people on your child's behalf for reasons of health/safety which has the potential to make people bristle or even be offended, you can't not do this because of your own discomfort.
Look up some assertiveness advice online especially videos where scenarios are worked through.
Honestly it's REALLY important that you learn to speak up for your child - your dp too.
You need to find that inner "mother bear" protecting her cub.
Its also, as you recognise yourself, better to raise issues calmly, politely but assertively than bottle it up until you end up letting rip because that will cause more issues and you won't be taken seriously.
And tell dp to quit trying to put you in the role of the bad guy! "I'll talk to her if you want " indeed!
NO! You'll talk to her because you're a father protecting your family from a woman who's seriously overstepping boundaries and causing offence and anxiety as a result! Not because his dp has "nagged" him into doing so!
The study about sucking dummies helping immune system is a very small study.
Re only taking an interest at certain points/in certain ways - she's only doing so with the things that are "public" that she can advertise, it's all for show "what a fab granny I am they couldn't cope without me" it's not about ds' needs or your needs at all!
Competitive grannying!