Imagine you are in a park or on a beach. A couple next to you give a cookie to their toddler. The kid drops it and picks it up again, with the full intention of going on eating. Two possibilities. One or both of the parents react with horror, tearing the cookie from the child's hand and throwing it in the garbage, whether or not there is another cookie to substitute. Alternatively, the parents look on indifferently and return to their adult conversation.
We all know how to interpret these two cases. In the first instance, we have the parents of a first or only child. In the second instance, we have the parents of a kid down the birth order. They could well be the same people over time, and the implication is not that the first are better than the second. It is probably a matter of the second pair being more experienced or tired or whatever.
Obviously these alternative behaviours are going to make a big difference to the children. Siblings tend to be raised differently, that is going to matter for personalities and – as Time editor and writer Jeffrey Kluger argues in The Sibling Effect – that is before you even get to the ways in which siblings themselves work together or against each other, moulding themselves into the kinds of people they are going to be in adulthood.
Kluger covers a lot of ground, presenting findings (in a non-technical manner) about personalities and relationships, in childhood and later. There is some reference to related themes in the animal world, but not much. What is much discussed, and is a real strength of the book, is the ways in the Western world that sibling relationships are being so shaken up by separation and divorce. One year, a child can be the king in the family, the oldest and most cherished. Then, a mere year or two later, he or she is down the pecking order with step-siblings now lording it over everyone. Kluger is good on the tensions that this sort of thing brings on and compromises that are necessary to go on functioning.
The book presents no real, overall binding theory. Probably the best-known recent treatment of sibling relationships – mentioned often by Kluger – is that of historian and psychologist Frank Sulloway, who argues that birth order is crucial. Firstborns tend to be successful but rather restrained. Younger sibs tend to be risk-takers and rebels. Sulloway argues that this is crucial right through history, being, for instance, a major factor in the Protestant Reformation. Breaking from Rome was less a matter of geography – distance from the centre – and more the fact that dissenting countries had social systems that encouraged younger sons to go into the church.
Of course, the trouble with overarching theories about such things as sibling relationships and personalities is, as Kluger notes, no sooner do you have a nice hypothesis than reality breaks in uncomfortably. Take the Royal Family. The Queen and her sister Margaret surely fit the Sulloway pattern, the former being staid, hard-working and successful, and the latter breaking from all of the constraints. But then you think of the generation before them. The eldest son, David (Edward VIII), was the rebel who refused to go along. The second son, Bertie (George VI), was the one who was responsible and diligent and all of the rest: the complete counterexample.
I do think that Kluger might have made more reference to evolutionary biology. That is a science that takes things like birth order very seriously. To be fair, though, he does talk briefly of some of the interesting work on birth order and sexual orientation, and whether coming further down the list makes one more likely to be gay, and how this could be a function of the genes, perhaps triggering hormonal differences before birth. He mentions speculations about how biology – natural selection, particularly – might be involved.
Here, as throughout the book, Kluger links the discussion to his own family, in this case to a gay brother and the role he has played in the family. Over all, there is a tone of melancholy, for it is clear that Kluger's was a deeply dysfunctional family – an abusive father who left when the children were young and who had a second family that was not told of the first, and a mother so addicted to pills that the children had to have her committed.
And, in a way, this brings me back to my little example at the beginning of this review. On the evidence of Kluger's family, the relationships between the children was very important, particularly in protecting each other from the parents and their actions. But his story strongly suggests that it is the parents who make the running in families and that the children are playing catch-up. Although let us not forget that when dealing with families, there are exceptions to every rule, so who knows whether the Kluger family was typical?
Michael Ruse is the eldest of five children. He is a perfect exemplar of birth order theory, being hard-working, conventional and terrified that he never lives up to his parents' expectations.