You know what, contrary to popular beliefs, being an only child isn't lonely at all.
And no, it doesn't make you a loner and/or an introvert at all. Nor does it make you clingy and spoiled.
My mum and dad never spoil me. Sometimes they do nice surprises and stuff but I don't think they've ever spoiled me. I don't really like it when people say so, to be honest.
Also, I don't think I'm ever lonely because I don't really know how it feels to live otherwise. I never had any brothers and sisters, so I can't say that I'm lonely when I'm alone.
I actually quite like it. Growing up, I found that in the end, I always need my personal space no matter how much time I've spend the day with other people. Like I may need an hour of personal time for every... say six hours of socialising.
I can't say I never wished I had a sibling, an older one that is, but I think I like being an only child after all.
Besides, I have my little cousins to babysit whenever I want the experience. :p