My advice – regardless of what your wife does, once she is finished you then do / say what you were going to.
TBF if she is with him all day she may just be running on auto pilot.
However, if you have discussed this issue and she dismissed it and continues – I would say take firm, calm action and do you.
I found when this happened on occasions that taking the little one(s) out and having alone time with them stopped all this.