How many brothers and sisters do Americans aged 18 or older have? The 2018 General Social Survey asks about siblings with the question, ...

Among the nation's 74 million children under age 18, more than three out of four (78 percent) live with siblings. Only 22 percent do not...

Nearly 80 percent of children under age 18 live with siblings, according to the Census Bureau. But no one has examined how the presence of s...