The IFS institute found that there is "little or no evidence" that the parents' marital status affects a child's social or cognitive development. Instead, they say, children are more impacted by their parents' level of education. If both parents have high levels of education, it makes no difference whether they're married or just living together. Census Data Shows College Educated Couples Less Likely To Cohabit
While children born to unmarried parents are less cognitively developed than children born to married parents, researchers found, they believe it's a result of the parents' low levels of education — not their decision not to tie the knot.
"It is true that married couples are on average more cognitively and emotionally successful than children born to cohabiting couples. But careful analysis shows that this largely reflects the differences between the types of people who decide to get married and those who don't," said Ellen Greaves, a research economist at the IFS. Why Happy Marriages Produce Happy Kids
Do you think children grow up smarter if their parents are married?