How to teach an only child to socialize.

So I'm about to have my first and possibly, hopefully, only child.Thinking back on all the only-children I've babysat, these kids tend to be bad at socializing with peers and sharing. IMO, they kind of expected their friends and peers to treat them as their parents do. ( You know, everything they say and is far more important and their opinions are generally more 'correct'.)Basically, they never had any siblings to tell them that nobody is here for their shit. And friends tend to just avoid them or just you know take them in small doses. Like whenever you say something they don't agree with or like they may just see it as see it as you being ruse or mean.Ok I know this is not every only-child. But I feel like I've seen these traits in far more of them than with people who have siblings in their age range.How do I attempt to teach my child these skills. I grew up with a couple of siblings and I kind of feel like it would be selfish of me to not give my child at least one of their own. But at the same time I don't see us ever having more.Any tips are gratefully accepted or you can feel free to tell me I'm crazy and that it's nothing to worry about.Thanks! via /r/Parenting http://ift.tt/2ixLoHl