By "small" do you mean only-child?
I've noticed most if not all of your topics here are on this subject, but am not sure why.
To answer your question: I think I experienced both the best and worst of -both-sides of the issue. Meaning: as my siblings were around a generation older than me, I knew what it was like to "have" siblings, and knew what it was like to "not have" them.
From my POV (then and now), having was better than not having.
Growing up alone was a very lonely experience- even more so because all of my friends and neighbors grew up with brothers/sisters.
Now that I think about it, I can't think of a single benefit of those years when I was the only child.