All right, let's do a thing.
With the rise of social and cultural history in the decades after World War II came attention to the idea that childhood has a history: that what it meant to be a child, within a family and within society, meant different things at different times even in the West. Two studies have proved both enormously influential and enormously controversial: Philippe Aries, Centuries of Childhood and Lawrence Stone, Family, Sex, and Marriage in England, 1500-1800.
Aries argued that the high rate of childhood and especially infant mortality prior to the late 17th century meant medieval people, including parents, could not emotionally afford to invest in their children. The Middle Ages did not have the concept ("sentiment") of childhood as a distinct stage of life with its own material culture, focus, and theory: children were little adults. Stone argues that the nuclear family demonstrates the birth of "affective individualism" through the middle classes above all in the 18th century, with aristocratic and working-class families displaying the trend in the 19th. He traces a tidy progression. Medieval families were utilitarian, harsh, paying little attention to emotional needs for affective connections. From 1500 on, familes neatly progressed from 'open' families flowing in and out of broader kinship networks and godfamilies, to a more closed-off patriarchal family that saw itself as a cohesive unit with all members contributing to that unit, to finally, a closed nuclear family based on marriage ties of love with attention to the needs and desires of individuals within (including children).
The underlying point, that families and children are something to historicize, is incredibly important. Nevertheless, some scholars reacted quite vigorously to the implications of these arguments, like that medieval parents couldn't let themselves care about their children.
Digging way way back to my undergraduate notes (!), the key early response to Stone that covers the same time period is Linda Pollack, Forgotten Children: Parent-Child Relations, 1500-1900. In contrast to Stone's argument for change over time, she uses descriptive sources like newspaper accounts, autobiographies, and diaries to argue (1) that interpersonal relations within families did NOT change radically in the 18th century and (2) that early modern parents loved their children. An important weakness in her thesis is her reliance on diaries from the 18th century in particular--exactly the period where Stone did see affection. (They aren't all of her sources, but some of her most central).
Hugh Cunningham, Children and Childhood in Western Society Since 1500, takes Pollack as a starting point (early modern parents loved their children) and looks at how theories of education both reflect and further push the cohesion of childhood as a concept, starting with the Protestant and Catholic Reformations. So he is basically pushing the time frame back.
Alan MacFarlane takes up Stone's thesis, specifically, in a review essay that is available for free online! However, his does not take the form of a history of childhood: instead, he critiques Stone's underlying teleology of a neat progression in social/intellectual history, as well as pointing out the really flabbergasting interpretive errors Stone makes.
And, indeed, medievalists love a good challenge from scholars in other eras working with medieval sources or making medieval assumptions. Two studies of medieval childhood in particular address Aries and Stone with respect to the matter of childhood as a distinct, cared-about social construct, and whether medieval parents loved their children.
Shulamith Shahar, Childhood in the Middle Ages, sketches out a medieval theory of children and attempts to get at a children's culture. A lot of her points are backed up by Barbara Hanawalt's research in Growing Up in Medieval London and The Ties That Bound: Peasant Families in Medieval England (which is a great read).
More recently, Elisheva Baumgarten's exciting Mothers and Children: Jewish Family Life in Medieval Europe looks at children within the context of families, Jewish ritual life, and Jewish-Christian relations in medieval France/Germany. She shows how firmly children mattered in the Jewish communities of Ashkenaz, and traces out connections to similar sentiments among Christians. (This is one of my favorite medieval books to recommend--it's creative, unique, a great demonstration of solid comparative historiography, and IMHO the material is fascinating.)
Except for Baumgarten, most of these are older. Nevertheless, they seem to supply the foundational arguments that later books and articles on the topic adopt as the basic possible starting points for the history of childhood before industrialization.
Tagging /u/sunagainstgold as you've critiqued Stone's opinions before.