The best part about growing up an only child is that you don't have to share your toys with anyone else. This has an upside and a downside. You tend to take better care of your stuff, 'cause you know that if it is to be broken, it will be done by you and you alone. However, it also makes you selfish when it comes to sharing with others as you grow older.
There are other good news, bad news things about being an only child. You get all the love your parents have to give a child. But you're the only one there to take care of them when they get old and feeble. And you're the only there one to bury them.
You tend to be more successful at whatever you decide to do, but you can also be ruthless and quite cold to those you step on while reaching this plateau. I say this only to warn you folks up there above me on the Best Users List. . .