Twenty-five years ago, Leonore Davidoff and Catherine Hall pioneered the study of the middle-class family with the publication of Family Fortunes: Men and Women of the English Middle Class, 1780–1850 (1987). Numerous studies of parental and marital relations followed, but relatively few concentrated on lateral kin ties (siblings and cousins). Davidoff has now filled that gap with an elegant study of “life’s longest relationship” (2), into which she includes not only siblings but also cousins, aunts, and uncles. Her time frame is the long nineteenth century, and she is, again, concerned only with the bourgeoisie. Although most of the examples are British, she discusses families from North America and Europe as needed.

Thicker than Water begins with four chapters of background information. Those familiar with family history can safely skip these; indeed, chapter 1, which surveys studies of siblings by the social sciences, does not fit well with the rest of the book. Davidoff dubs the early and mid-Victorian period as the age of the “long family” featuring many children and, thus, in the second generation, the potential for scores of cousins, aunts, and uncles. A family of seven siblings who each had eight children would, for example, result in each child having 128 first cousins and twenty-eight uncles and aunts (84). These crowded households left much less room privacy than historians normally attribute to the middle-class home and gave scope for a great deal of influence of siblings on child development. Children’s experiences depended on birth order and gender but also accidents of fate (as in the death of an older sibling) or the quirky preferences of wider kin. The biggest change over time was the fall in fertility in the late-Victorian period, which altered not only the number of siblings in the family but, inevitably, the number of cousins, aunts, and uncles.

The second section of the book is a wide-scale survey of the importance of sibling bonds. Davidoff argues that a large number of siblings meant that all children stressed “fairness” as the goal: “no one got more than their share, cheating and lying were frowned upon” (114). Despite siblings having different levels of power, usually based on birth order or gender, loyalty to the group was highly valued, and alliances shifted over time. As siblings grew up, gender differences became more central since boys went to school and girls stayed behind until marriage. As they aged, brothers and sisters had to negotiate how to stay in touch; exceptionally close siblings often found these transitions wrenching. In contrast, those who did not marry might set up households together; in 1881, 11 percent of women and 8 percent of men lived in households with at least one sibling (141). Coresident sisters ran schools or millinery shops; brothers, however, would set up formal business partnerships, but they lived together less often. The stereotype of the unmarried maiden aunt living with a married sibling had a basis in fact, and many of these women did heroic amounts of child-care and emotional work, a point also stressed in a separate chapter on aunts, uncles, and cousins. Aunts frequently stepped in to assume a maternal role upon the death of the mother of the family, but their help need not have been this day to day. Wider kin found jobs and marriage partners and offered safe havens during troubled times. They also acted as both negative and positive alternative role models. Cousin relationships varied enormously, with some as close as siblings and others quite distant. Like aunts and uncles, cousins gave emotional support and made business contacts. Networks of long families benefited the kin group financially; as one of Davidoff’s examples wrote, “it’s a very good thing to have cousins” (188).

The third section contains three thematic chapters that read as separate essays on incest, “close marriages,” and the loss of siblings. Davidoff stresses emotional (rather than physical) intimacy in her chapter on incest, using William and Dorothy Wordsworth as a case study. She refuses to try to determine the level of intimacy in their relationship, concluding only that “their ‘twinship of souls’ meant that in a sense each completed the other” (215). In this section, too, she revisits the deceased wife’s sister controversy but has less on sexual relationships between uncles and nieces or nephews and aunts. Another chapter explores “close marriages,” those with multiple ties (as when two brothers married two sisters or cousin marriage). The early to mid-Victorian period was the heyday of these alliances because the sheer number of siblings and cousins made intermarriage easy and economically useful. Scientific and psychological studies eventually cast doubt on the wisdom of cousin marriage, and the decreasing number of siblings, in addition to changes in business culture, meant that the incidents of these marriages lessened by the early twentieth century.

In the last chapter, Davidoff sensitively paints the many different reactions possible to the death of a sibling, especially at a young age. These included survivor’s guilt for those left alive and confusion in identity formation for “replacement” children. Siblings, adult or child, expressed profound sorrow at the loss of brothers and sisters. This grief was most poignant during World War I; late-Victorian families had fewer children, so the losses, already staggering, were proportionately greater. In the third section, Davidoff also includes chapters with case studies of particularly intense sibling bonds, the first between William Gladstone and his sisters Anne and Helen and the second of the Freud family. These portraits are well drawn but contain few surprises, as they go over well-trodden ground.

A study of siblings and cousins has been long overdue in British family history, and Davidoff is a sensitive reader of the letters, diaries, autobiographies, and biographies that make up the bulk of the sources. Additionally, she uses insights from psychology and anthropology to good effect, and her writing is smooth and, at times, touching. Her book fits well into recent studies, for example, by Barry Reay and Adam Kuper, that emphasize the importance of wider kin in the Victorian era. In the middle class, sisters and brothers, cousins, and aunts and uncles all had important roles in rearing children, finding schools and jobs for them, marrying them off, and helping them survive various crises. In short, the stress on lateral relationship in children’s development, rather than the parent-child dyad, is most welcome.

All the same, the study will be a starting point, not an end. Although Davidoff sets her examples in a wider context, she primarily uses well-known groups of siblings, many of whom included famous artists, authors, or politicians. Can such unusual people stand in for the bulk of the middle classes? She also might have been better served to focus more tightly on Britain. How much intermittent stories like those of the Van Goghs and the Freuds can illustrate about European siblings is an open question. Readers also might be disappointed that her conclusions rarely challenge her initial sketches of siblings and cousins in Family Fortunes, although, of course, are much amplified (Davidoff and Hall, Family Fortunes, 348–56). In addition, she declines to take any stand on some controversies (as with the Wordsworths). Nonetheless, Thicker than Water is beautifully produced and written and begins a historically significant conversation. Future histories will be able to elaborate on—and offer challenges to—its conclusions.