In the first week of March, 2016, Virginia banned child marriage completely. Why? Here's how journalist Libby Nelson describes it at Vox:
"Children as young as 13 can get married in Virginia, if the girl is pregnant or the couple has parental permission. And since 2004, thousands of teenagers have gotten married in the state, including more than 200 who were 15 or younger. Nearly all of those married children were girls.
The Virginia legislature just changed that, voting in favor of a bill that would require a judge's approval for anyone under age 18 to marry and forbidding marriage for teenagers under 16. It now goes to the governor's desk. While allowing children to marry might seem barbaric and backward, Virginia is far from alone. Most states still allow children to marry if there's a pregnancy involved, or with the consent of their parents and a judge.
Advocacy groups argue that allowing younger teenagers to marry is a terrible idea - parents might be not just consenting but forcing their children to marry. Judges in New York, at least, have approved marriages where the age differences between the partners would otherwise lead to an investigation of charges of statutory rape. It's illegal in New York for an adult to have sex with someone under 16, even if the sex is consensual. Judges still allowed teenagers younger than 16 to marry adults, Fraidy Reiss, the director of the nonprofit Unchained at Last, wrote in a New York Times op-ed in 2015: 'In 2011 alone, a 14-year-old married a 26-year-old, a 15-year-old was wed to a 28-year-old, another 15-year-old was wed to a 25-year-old and a 15-year-old married someone age '35 to 39.' All of those marriages were approved by New York judges.' Virginia might not be the last state to toughen its child marriage laws. Maryland and New York are considering similar bills."
Everything a state does must work for the best interests of the child, as set out at Tracing the Foundations of the Best Interest of the Child Standard in American Jurisprudence. Family restoration requires protecting children from adults who may prey on them in underage marriage.