I am an only also and adopted.
My mom lost four babies. The last one was full term but she had Uremnic poisoning (spelling on that--not sure), and nearly died she was so ill. The baby also had it and died two days later.
I have always known I was adopted and it was never an issue. I feel my soul was with the parents it was suppose to be, and that the biological parent was simply a vehicle for that to happen.
I do have to say that many times 'onlie's' are created out of circumstance and not choice. And I often wonder why we are thought of as such an oddity. People always say did you like being and only child. I never hear anyone ask that of anyone born to a family with siblings. I have also been asked through the years was I lonely. My favorite question for the only is do you thnk you were spolied. My reply is always the same---my parents had no other children to do for--I was the only one---they only had to pay for one college education, they only had to buy my clothes, they only had to take me on vacation. Sorry but the only brings the cost ration way down in the family---so I did benefit from my circumstances----that does not make me spoiled.
Anyway what do the few other onlie's here think.