Brother (M16) doesn't talk to anyone

I'm sorry if this is the wrong place to post, but I don't know where else I could go.My (M25) little brother (M16) has always been antisocial. But I'm worried that he's getting older and that life will be hard for him because of this.It's not that he's shy or anything, it's just that if I ever ask him a question to start conversation he always answers with very short responses. I even make sure not to ask 'yes' or 'no' questions and he still manages to not keep the conversation going.He's never had a girlfriend and I can't even imagine what he would be like on a date. It would be total silence. He doesn't really have friends or even one best friend and I started bringing him into my circle to see if it would help him open up and its helped but very little.He's not just like this with me, but he acts this way towards everyone including my mom. I feel like I don't really know him because he never talks about stuff, or what he does during the day, or his opinions on anything. He is completely to himself. I honestly don't even know if he likes me or not.He is overweight, so I'm sure his self esteem isn't very high. When he is home he spends his total day in front of the computer.He doesn't show symptoms of autism or any other mental condition. But I worry about my little brother, and I'm scared that life outside of high school is going to be extremely tough on him.Can anyone relate or send advice.tl;dr Brother is extremely antisocial, doesn't ever talk, and I don't know him even though I hang out with him all the time. Worried about how his life will be as he grows. via /r/Parenting http://ift.tt/2dEVBAs