EW
last weekend was a turning point for all in your family.
I alway try to see the learning from each issue.
The two hour talk would allow your son to see how seriously the situation is.He would have to process the conclusions.You had your husband and us to to share your feelings with....He was out for the day at golf..trying to cope with a baby and really not on the same page as you were.
Imagine the years to come and all child rearing issues Anniya will bring.It would be ideal if ground rules could be established that good manners be maintained.If not same old... same old will repeat.
Then part of the time is spent in trying to re establish ground rules.

So hugs for son when he comes and positive reinforcment about his parenting..drip drip driping tap..it works in class slowly but its worth trying in a home situation.

Disempowering is destructive and I feel DIL has disempowered
your son.His hopes and dreams.
Often a time of stress allows the redrawing of power and
what is accepted...seems to me you were able to say that its for the love of Anniya that you ask about her and share concerns.
Adopt me if you like EW I feel in need of support often.
Mountaina ash