Early morning deep thoughts...

If the relationships that we have within our own families are the ones on which we base all others, and if we bear the burden of reliving or improving upon or retroceding into the basic structures that we have ingrained in our being what happens to only children?

I ask this only because I was just musing upon the different types of amorous relationships/ partnerships in the observable universe.

Couples tend to fall into varying categories, and we tend to find ourselves seeking some sort of replacement or stand-in, it would seem, such as: (and of course these are only the most typical, no time for exhaustive studies, I mean, really, I don't do this for a living:) And of course there are variations on these themes (choose your gender and sexual preference, I think these models might still work - tragically)

Father-daughter (the one is always seeking a father figure to lead the way with a strong hand... say)
Mother-son (where one is constantly taking care of everything, and clucking about it...)

but here is perhaps the most perplexing, and confusing of all
brother-sister: (where love grows into something that is comfortable, and caring and totally asexual)

Hence... my question what happens if you have no siblings to speak of? Also, what if you would really rather replace yourself? Hmmm. No problems being solved here!