Sunday is Father’s Day, and not all homes have a father living in them. We have a fatherhood problem in this country, and it’s nothing to laugh about. According to the U.S. Census Bureau, almost 18 million children in the U.S., or nearly 1 in 4, live without a biological father, stepfather or adoptive father in the home. That’s enough children to fill New York City twice or Los Angeles four times over, according to one source. Statistics from th…