Over the last two decades, the share of U.S. children under age 18 who live in a multigenerational household (with a grandparent and parent) has increased dramatically. Yet we do not know whether this increase is a recent phenomenon or a return to earlier levels of coresidence. Using data from the decennial census from 1870 to 2010 and the 2018 American Community Survey, we examine historical trends in children’s multigenerational living arrangements, differences by race/ethnicity and education, and factors that explain the observed trends. We find that in 2018, 10% of U.S. children lived in a multigenerational household, a return to levels last observed in 1950. The current increase in multigenerational households began in 1980, when only 5% of children lived in such a household. Few differences in the prevalence of multigenerational coresidence by race/ethnicity or education existed in the early part of the twentieth century; racial/ethnic and education differences in coresidence are a more recent phenomena. Decomposition analyses do little to explain the decline in coresidence between 1940 and 1980, suggesting that unmeasured factors explain the decrease. Declines in marriage and in the share of White children most strongly explained the increase in multigenerational coresidence between 1980 and 2018. For White children with highly educated parents, factors explaining the increase in coresidence differ from other groups. Our findings suggest that the links between race/ethnicity and socioeconomic status and multigenerational coresidence have changed over time, and today the link between parental education and coresidence varies within racial/ethnic groups.

中文翻译：

---

生活在美国多代家庭中的儿童的历史趋势：1870-2018

在过去的二十年里，生活在多代家庭（有祖父母和父母）的美国 18 岁以下儿童的比例急剧增加。然而，我们不知道这种增加是最近出现的现象还是回到早期的同居水平。使用 1870 年至 2010 年的十年一次人口普查和 2018 年美国社区调查的数据，我们研究了儿童多代生活安排的历史趋势、种族/民族和教育的差异，以及解释观察到的趋势的因素。我们发现，2018 年，10% 的美国儿童生活在多代家庭中，回到了 1950 年的水平。目前多代家庭的增长始于 1980 年，当时只有 5% 的儿童生活在这样的家庭中。20 世纪早期，种族/民族或教育导致的多代同居流行率几乎没有差异；同居中的种族/族裔和教育差异是最近出现的现象。分解分析几乎无法解释 1940 年至 1980 年间同居人数的下降，这表明未测量的因素可以解释这种下降。婚姻和白人儿童比例的下降最有力地解释了 1980 年至 2018 年间多代同住的增加。对于父母受过高等教育的白人儿童，解释同住增加的因素与其他群体不同。我们的研究结果表明，种族/民族与社会经济地位和多代同居之间的联系随着时间的推移而发生了变化，