Oh Hell No! He would not be moving in my house. Where is his folks at? A lot of questions for me to ask. You know what is going to happen. She will get knocked up fairly fast and you are going to foot the bill. When they are under your roof, you are the boss so act like it. Put your foot down and do not give. If your wife is all for it, give her arse the boot too. Man up and make good decisions. Letting him in your house will cause CHAOS and you will suffer the most.
