When you were in college, how many times did you call home for comfort, advice, a recipe -- and maybe some help paying that long-distance bill you ran up while breaking up with your boy/girlfriend? Or, say you went to work after high school. Did your folks lend you a hand with that first month's security deposit on a new apartment? Bring you a meal and a care package of pots, pans, and laundry detergent?

I don't remember any of my friends waking up on their 18th birthday and being told, "We've really enjoyed being your parents. Now, pack your stuff, we're changing the locks and getting an unlisted number. Have a nice life." But, in effect, that's what most state child welfare bureaucracies say to their children -- the thousands of young men and women who reach the age of 18 while in foster care.

While middle class kids are enjoying a cushy new stage of life sometimes referred to by the truly horrible name of "adultolescence" well into their mid-twenties, the ones who most need support are basically being ushered to the curb.

This isn't true in every state. A few enlightened localities -- among them, Illinois and the District of Columbia -- allow children in care to remain in state custody until the age of 21. It is the right thing to do -- not just because it is fair, but because it makes a difference.

Mark Courtney, director of the Chapin Hall Center for Children, is doing research into how young people leaving foster care as adults fare in the real world. Working with a longitudinal study that includes children in Illinois, Iowa, and Wisconsin, he's been able to look at what happens to kids who are "emancipated" at 18 (in Iowa and Wisconsin) and those who choose to remain in the system longer (in Illinois).

Here's what he's found: at age 19, fully 72 percent of foster youth in Illinois have chosen to remain in custody of the state.

Among these older youth, over 60 percent of those still in care are receiving educational support or job training...compared to only 44 percent of those who left care. Those in care are three times to be in community or four-year college, and in fact their college participation rates are close to those of kids their age who have never been in foster care. Those who leave care are more likely to be arrested and incarcerated; more likely to suffer from an untreated mental health disorder; more likely to be both unemployed and not in school.

"It calls into question the idea that these young people are ready to be on their own at 18," Courtney remarked at a recent panel discussion.

Well, are any young people ready to be on their own -- really, truly, on their own -- at 18? Were you? I wasn't.

Courtney says that the young people he studied are optimistic about their futures, and often do have supportive relationships with adults and family members. What they don't have is health insurance, they don't have a diploma, and they don't have what they need to turn their optimism into a solid grounding for adulthood.

Someone could probably do -- has probably done -- an economic analysis proving that allowing children to stay in state custody until they turn 21 or finish college or job training is a long-term money-saver that keeps kids out of jail and turns more of them into taxpayers. But we don't need to know that, to know what is right: when the state decides to step into a family and remove a child, it assumes a moral responsibility that can't be terminated with the turning of a calendar page.