How the Definition of an American Family Has Changed

There were fewer nuclear families and many more alternative arrangements, such as unmarried parents

The transformation of the American family deepened over the past decade, as an increasingly diverse array of arrangements replaced the married-with-children paradigm.

Marriage is playing a smaller role within families, as more people delay tying the knot, live together without marrying or divorce. One exception is same-sex couples, who are marrying at higher rates after winning the nationwide right in a 2015 Supreme Court ruling. Separately, multigenerational households are becoming more prevalent, with more children growing...