On the eve of our wedding, my MIL was getting upset (good start, eh?!). I gave her a hug and to lighten the mood (because weddings are a happy occasion, no?!) I said 'don't worry, I'll look after him for you'.
She gripped me by the shoulders, put her face right up to mine and said intensely 'oh no no no. We will have to share him'.
Thankfully I had wine on board, skipped away to my mum's car and had a giggle with her about it on the way home. DH was mortified.
Try not to start your MIL/DIL relationship by being bonkers possessive and crying throughout 90% of the wedding preparations and event itself, and you will probably be fine. 😂
Things with my MIL escalated when I had DD. The good old BF vs FF debate, asking me if I really had PND (no, the GP just gives out ADs for fun these days!). Collaring DH when I was in the toilet and asking him whether he agreed with the feeding choices we were making for DD, trying to buy baby food for DD (we did BLW; she eventually succeeded in trying to feed her a jar when I wasn't there at 12 months old, DD apparently looked at her as if she was mad and ate DH's sandwich).
The way to have a good relationship with another reasonable person is easy; just ask them what works for them and LISTEN to the response! Remember that they may well have different values and principles to you, ask what they are and try and accommodate them. Don't try and take over. That goes for both MILs and DILs.
(My MIL does it to her daughter as well, so I guess I can't complain too much as she gets the worst end of the stick. MIL cut the cord instead of BIL, did first baths, feeds, first day at school, SIL is pushed out a lot. She relies on MIL for childcare and feels stuck. We avoided this by living a long way away).