My son got married 6 months ago and he and his wife are expecting a child

I was 16 when I met my wife, we were married when I was 17 and she was 15. We were a young family but we made it work. We had three kids together as well. We're coming from a poor family, just a simple family, nothing too complicated here. We're a Mexican family, but we grew up in the United States. My family is here illegally, but because of the laws there wasn't any problems. I know that this is not a legal case, but I am Mexican so I think that it's fine.<br><br>One day, I was 22 and my wife was 21. We were living with my in-laws. My FIL [father in law] always had a mistrust in me and started to say bad things about me with my wife. Of course, just as my wife got pregnant of our first child, my FIL told her that it couldn't be my child. My FIL asked my wife to go to the hospital and ask for a DNA test. I agreed, so we went to do it.<br><br>After a month of waiting, the results came back. It said that it was a 0% chance that I am the father. I was shocked, and I felt so angry and betrayed that my wife could do that. Of course she cheats, she will say that we were doing **that** just to get herself pregnant anyway, just like my FIL said. Well, he was right and that was all that mattered.<br><br>My son was born premature. I was there with my wife and I'm sure that some of you will see this as a really messed up thing. I pretended that her child was mine. I was a little upset, but I didn't want to hurt my son. My wife was also very upset, just like me. However, my in-laws are involved in our lives and we were living with them, so it was hard to get a divorce and to explain the situation to anyone. My wife also begged me to not leave her, so she also begged me to act like her son was mine.<br><br>So, my "son" just got married 6 months ago and now he and his wife are gonna have a child. My son is a really happy guy and he also doesn't know that I am not his real father. I don't know what to do at this point.<br><br>When my son was 14, my FIL died. So, after he died my wife and I got a divorce and she moved out. I am still alone though. I am not a very attractive man, but I am not really broken or anything, I am happy. I am a good dad to my kids. But to my eldest son, it's complicated, because I am still acting like his dad and I am involved in his life. I know that he is not my son, so I don't care if he knows my family or not. I do know that he loves me though, and I also love him but not in a fatherly way, of course.<br><br>I am 41 now and my son is 18 years old. I know that this will not last forever, but I really don't think that I need to tell him anything. I don't know if he will get mad at me or not, but I don't care either way. I just want to see him happy and I don't care as long as he is happy, because I am happy with what I have at the moment.<br><br>I know that this may sound messed up to you. You may call me a coward, or an asshole, etc., but I really don't care. I am happy, my son is happy, and everyone else is happy, too, that's all what mattered.<br><br>&#x200B;