Does your decree say no overnight guests of opposite sex while children are present?
That is a good question.
No it does not and I wish it did. We had shared custody (6 months with each parent) and XH ended up living with another woman, unmarried, with my children under the same roof.
I will say that over a decade later my children are thus far pretty picky about their dating behavior. As long as your child has one solid good example then they will do all right. The stark contrast between your life and demeanor as compared to XH's will not be lost on them as they grow up.
I also think you've done well to raise an objection (since it IS in your divorce decree). However you are not able to prove whether OW is going to be "present" overnight or not without going down there and stalking them, hiring a PI, or putting your DS on the stand as a witness against his own father.
It is my opinion (worth what you paid for it, and I do realize that) that to pursue this further would be a waste of money and energy. I do think you had an obligation to raise an objection to the vacation with OW in the first place.
If XH and OW rent two rooms or whatever, that will have to be good enough.
The thing is, the judge is going to believe their story of "But your honor, we had separate rooms!" and legally he can't do anything. He's bound by the law. You are stuck with having to hire a PI or stalk them or put your son on the stand regardless of whether or not you take this to court now. XH is just going to lie and the judge has no choice but to believe him.
AFTER the vacation.. well, that's another story.
