Musings on Siblings

So siblings are very important in our society. What percentage of people in the world are siblings? Are there large variations in this figure? Are these variations well explained?

Is there a variation in your probability of being an only child based on gender? Do we see that people tend to be more likely to have just a son than just a girl? Does this stem from expectations about being able to work to support the parents and generally that sons will be more successful and better descendants? Is there an argument to be made that parents want daughters to be able to marry up? Surely this would be unlikely in the West (or at least my perception of the West) wherein marrying up is a far more fickle notion thna it was previously.

What about parents and the number of offspring that they have? Everyone is familiar (or at least I, the older brother of twins) that if you are a twin, then you are more likely to have a twin. Is this fact actually true? Is there something to be said for if your parents are onlyn children, then you are more likely to be an only child? Is there something to be said for if your parents have lots of siblings, then you are more likely to have siblings. There are arguments for and against this latter point: An argument for would be that your parents would have appreciated growing up around their numerous siblings and would want the same for their kids. However if your parents actually felt that having that many children is detrimental to the kids, then they may consider otherwise.

Of course there is an underlying assumption here about peoples ability to control conception universally. Generally in my strata, there is access to contraceptives and there is access to Plan B and access to Abortion however people may have personal reasons against using some of these methods to their detriment. I must reiterate my view ‘The invention/profileration of the contraceptive is one of the greatest achievements of mankind’. Is this counter-intuitive due to surely for the purposes of mankind, large production of offspring is advisory? Am I arguing on the merits of individuals happiness (and by proxy, health) rather than the heath of the species? Would the conclusion change if we cared about the latter? Not neccesarily, as overpopulation is a serious issue that we could face and it definitely holds true for natural populations as any maths/biology student just faced with teh Volterra-Lotta equations could tell you.

Possibly comment in the abstract about eugenics/ anti-natalism. Antinatalism is an interesting viewpoint that ‘birth is highly non consentual’ and how can we believe that our children will be happy consequently. So given that by the act of birth, we will be likely introducing unhappiness into the system we should be far more considerate of when we have children. THen there are considerations about whether this is a policy that should be enacted by the government? Given that one can recognise that births can be inappropriate for the mother and the child to be and feel that for the sake of society who would have to support an individual, a soul, another mouth to feed for what purpose, should the government come forth and enact policies on when people can bear children? What would such policies even look like? Would we vet people by intelligence, wealth and capacity to support a child? Would we allow people to have their third child before we allowed others to have their first child? Should we even live in a society where it’s questionable whether certain people should have children?

To answer that last question, everyone would emphatically agree that we shouldn’t live in a society where people who want to should be denied having children purely due to financial reasons where others can. However if we believe in some state sanctioned anti-natalism, then presumably we believe even in a Communist Utopia that there should be some restrictions around child rearing for the sake of the wider society.

I’ve somewhat been lost from my original point around siblings. I am also very interested in the social, mating and general behaviours of people depending on their position in the sibling hierarchy. This stems from a personal interest as a child, an eldest child and as a sibling but this was particularly prompted from a discussion wiht my friends about how comparatively few eldest children seem to be at Cambridge (or at least in my social circle). There is also an interesting discussion about similarity between only children and eldest children.

Do eldest children bear more in common with only children than other children with siblings and do they even bear more in common with only children than other children with siblings? Remember there is a heavy confounding factor here of the age difference between the children that comes very apparent in this discussion as it is quite likely that the eldest child may have lived for a substanial time as an only child and this will play an important developmental effect.