[Ed. – So basically, Grandma was right.]
Also complicating low-income single parenthood in America is what the experts call “multipartner fertility.” Both divorced and never-married Americans are more likely to repartner and start “second families” than Europeans, but the trend is far more common among unmarried parents. According to data from the Fragile Families and Child Wellbeing Study at Princeton and Columbia Universities, over 60 percent of low-income babies will have at least one half sibling when they are born; by the time they are 5, the proportion will have climbed to over 70 percent.
All of this would be of merely passing interest if it weren’t for the evidence that this kind of domestic churn is really bad news for kids. The more “transitions” experienced by a child — the arrival of a stepparent, a parental boyfriend or girlfriend, or a step- or half sibling — the more children are likely to have either emotional or academic problems, or both. (My own research indicates that boys, especially, suffer from these transitions.)
Part of the problem is that a nonresident father tends to fade out of his children’s lives if there’s a new man in his ex’s house or if he has children with a new partner. For logistical, emotional and financial reasons, his loyalty to his previous children slackens once he has a child with a new girlfriend or wife. Nor is it likely, from the overlooked child’s point of view, that a mother’s new boyfriend or husband can fill the gap. There’s substantial research showing that stepfathers are sometimes worse than none at all.
These realities help explain the meager results of government marriage promotion programs. It doesn’t make much sense to encourage, much less pressure, a couple with no shared history, interests or deep affection to marry. At any rate, given the prevalence of multipartner fertility it’s not clear, as one scholar asked in a paper, “who should marry whom.”