Children as an Irreversible Joint Project

Little children, little troubles; big children, big troubles.

— Russian proverb

A child is called a continuation of the parents. Then everyone is surprised when the continuation wants to live differently. Another formula is simpler still: children are an expensive pleasure. It correctly notices the sleepless nights, the money and the lost time, but it turns the child into a consumer good that has to pay for itself in the owner’s joy. A third version declares children an investment in old age. Historically that is plausible in societies without pensions and social protection. In societies with pension systems, a grown child may live on another continent while his taxes finance support for more than his own parents. Every metaphor sees one cash flow and loses the other participants.

The conflict starts before any parenting

In 1974, Robert Trivers described the conflict of interest between parents and offspring. A parent allocates resources between the current child, its brothers and sisters, possible future children and its own survival. The child values itself more highly: it is genetically identical to itself, and shares on average half of its gene variants with a sibling. The optimal amount of parental investment is higher for the child than for the parent. This is not a clash of personalities. It appears even in a loving family and requires no conscious calculation. An infant demands more attention than an adult can give without cost to himself. A teenager wants more autonomy than the parent considers safe. Both can be reasonable in terms of their own problems.

The word “selfishness” only gets in the way here. The model shows a mismatch of interests, not a moral defect.

David Haig proposed carrying the same logic inside pregnancy. The fetus gets half its genes from the mother and half from the father. Paternal genes are genetically indifferent to this woman’s future children by another man; maternal genes have an interest in spreading resources across pregnancies. The model predicts a conflict over the fetus’s nutrition and blood supply. Genomic imprinting gives especially clear examples: some genes work differently depending on which parent the copy came from. Placental signals change maternal metabolism, raise glucose availability and affect blood pressure, though an observed mechanism does not by itself prove every adaptationist reading of the model.

It does not follow from this model that the fetus is a parasite. A parasite belongs to a different reproductive lineage and does not share a large part of the host’s genes. Pregnancy is cooperation with a distributional conflict, not the takeover of someone else’s body. This is an important general pattern for families. Interests never coincide completely, but partial divergence does not cancel cooperation.

A project that cannot be re-signed

Before a child is born, future parents negotiate about a person who does not exist yet and about a workload both of them know only from other people’s stories. They can promise to split the nights, the illnesses and the career pauses evenly. After the birth, part of the investment is already irreversible, the child’s needs do not wait for a new round of negotiation, and the physiological load is distributed asymmetrically. This is an incomplete contract with a third participant who soon starts making demands of his own.

The main economic difficulty is that today’s actions change tomorrow’s bargaining power; the price of nappies is only the visible part. Whoever cuts back work first accumulates care experience faster while losing earnings. It becomes rational for the second one to work more, because his hour is now worth more on the market. Each decision confirms the previous one, and after a few years the originally temporary arrangement looks efficient: one really does know the children better, the other really does earn more. The system produces evidence of its own inevitability.

The child is not the object of the deal here. The economic model concerns how duties are distributed between adults and society. It is needed because a child’s interest cannot be put on hold while the parents work out who misread the old agreement.

Who pays for the next generation growing up

In a farming family, children took part in production fairly early and could become the main source of support in their parents’ old age. In industrial and post-industrial societies, a child receives education, housing and care for many years before entering the labour market. Part of the future benefit of raising children takes the form of positive externalities: taxes, human capital and support for common institutions are spread wider than the family, while a large share of the costs is concentrated on the parents. Pregnancy, the career break, the daily care and most direct expenses fall on one particular family, often unevenly inside it. That does not make a child a pure public good, and it does not make a childless person a free rider: the term refers only to the gap between private costs and public benefits.

If a society values these externalities and the private price is high, private decisions can yield fewer births and less investment in children than collective policy would prefer. Public education, children’s healthcare, paid leave and benefits shift part of the cost onto those who receive part of the future gain. This is an argument about who bears the costs, not a claim that the state should assign people a desirable number of children.

Research on parental wellbeing gives a mixed picture. Parenthood is associated with more meaning, but also with more stress. The size and sign of the association depend on age, whether the child was wanted, partnership, income and support. In cross-country comparisons, the parental “happiness penalty” is smaller where leave, childcare and employment protection lower the private price of parenthood, and in some samples it disappears. This is not a clean natural experiment: countries differ in culture and in many institutions at once, so the comparison does not prove the effect of any single policy. But the pattern limits the moral explanation: the burden of parenthood shifts noticeably with the design of the environment and is not a fixed property of the child.

Three different interests

Decisions about children are often discussed as if there were one family subject. In reality there are at least three levels. The child has an interest in safety, development and steadily growing autonomy. The parents have an interest in closeness, meaning, their own health, income and other children. Society has an interest in demography, human capital and the durability of its institutions. These overlap, but they do not automatically coincide. Public policy may aim at a higher birth rate when that is not in the family’s interest, while the future child cannot yet take part in the decision. A parent may want achievements that do not match the interest of the person the child has become. A child may demand a resource that destroys the parent’s health.

In the terms of a hard decision, the roles are also split. The parents make the decision and pay a large share of the early costs; the child lives with the consequences longest; society later collects part of the human capital that was created; the bodily and career costs may fall disproportionately on one parent. Calling all of this a single “family interest” means hiding the distribution of power and costs inside the grammar.

One metaphor does not fit every level. A child is neither the parents’ investment project nor a pure public good. He is a separate participant who is temporarily and radically dependent on others. Support for families is justified by the way the benefits and costs of raising children are spread across different people and different times, not by a demand that children pay off. The parents make the initial decision, but the child does not belong to their plan.

Main sources

Trivers, R. L. (1974). Parent-offspring conflict. American Zoologist, 14(1), 249–264.

Haig, D. (1993). Genetic conflicts in human pregnancy. Quarterly Review of Biology, 68(4), 495–532.

Nelson, S. K., Kushlev, K., & Lyubomirsky, S. (2014). The pains and pleasures of parenting. Psychological Bulletin, 140(3), 846–895.

Glass, J., Simon, R. W., & Andersson, M. A. (2016). Parenthood and happiness in 22 OECD countries. American Journal of Sociology, 122(3), 886–929.