I feel sorry for you. For inlaws to violate a married couple’s private time — the penalty should be Heavenly death. If they refuse to stop or get offended — they should die.
I have seen marriages and engagements end because of parental interefence. I have no mercy for such dispicable creatures.
Personally, I am not married but I have seen this many times with others. I will tell any lady’s parents upfront will they respect our privacy or interfere in our lives. If that offends them, well, that answers my question, doesn’t it?
In your situation, if they make an issue, would have prayed they die. Show no mercy to those who want to murder your marriage and shalom bayis. And I think a measure if their Gan Edan should be transfered to you for recompense. Of course, it goes without saying, no children you have will be named after them.