Oh dear moggie. Of course we all hope that the baptism goes well but be prepared. If your D's testimony is about her "troubled teenage years" you an bet you'll be in there somewhere.
She's treating you very badly and this is clearly being enabled, condoned and possibly encouraged by her in laws.
Of course you should be able to wear what you want but you probably realise that wearing trouser will be a good 'excuse' for her to have a go. I hope she doesn't but I'm sorry to say it is a distinct possibility.
We'll all be thinking of you and please let us know when you can, how it went.
Christmas lunch - AIBU?
Questions about my finances - bad manners?
Other people using my toilet - do you let them?