My wife and her brother are a little too close, kissing and hugging, regardless of my feelings. What should I do?

There are three ways. First, tell them frankly, "What do you think when others see you like this?" ? Second: talk to your wife about a powerful relationship when you sleep at night! And it can't happen again! Third: Find a few outsiders and laugh at them when they cuddle, and then you can say a few more words, hoping to help you.