My youngest child just turned 12, but I can still remember how hard it was when my children were babies: the lack of sleep, the colicky evenings, the diaper blow-outs, the meals eaten with one hand, the worry when they ran a fever. But I never had to worry about whether we’d have a place to sleep at night, or enough to eat, and I never tried to wash and reuse a disposable diaper because I couldn’t afford to buy more. For too many parents of infants, that’s not the case . In 2014, nearly one-quarter of all babies under the age of 1 were in poor families, as were more than one-third of Black...