About 1 in 4 U.S. children – nearly 19 million – have at least one parent with substance use disorder. This includes parents who misuse alcohol, marijuana, prescription opioids or illegal drugs. Our estimate reflects an increase of over 2 million children since 2020 and an increase of 10 million from an earlier estimate using data from 2009 to 2014.

Those are the key findings from a new study my colleagues and I...