At one point in time in America, living at home with mom and dad after crossing out of your teenage years and into your 20s was embarrassing and something that was generally avoided at all costs. And while hard times come and go, 20-somethings who were forced back into their parents' care worked their tails off until they could save up enough money to once again regain their freedom.

But, these days millennials seem to be embracing the free room and board provided by their parents. According to a new study from the Census Bureau, roughly one-third of all millennials live at home with their parents and one-fourth of them can't be bothered with enrolling in school or finding a job.

Of course, while living at home can help millennials cut down on costs, according to a new study from Nerd Wallet, it can also have a devastating impact on the retirement savings potential of their overly accommodating parental units...to the tune of a quarter million dollars. Here are some of the key takeaways from Nerd Wallet's survey:

Parents could miss out on almost a quarter-million dollars in retirement savings by paying their adult kids’ expenses: According to NerdWallet analysis, a parent’s retirement savings could be $227,000 higher if they chose to save the money that would otherwise go to their child’s living expenses and tuition. Parents paying college costs could be missing out on almost $80,000 in retirement savings: More than a quarter of parents of children 18 and older (28%) are paying or have paid for their adult children’s tuition or student loans. The average parent takes out $21,000 in loans for their child’s college education, but the hit to retirement savings is almost quadruple that amount. Most adult children are living with their parents for more than a year after they turn 18: Almost 3 in 5 parents with kids 18 and older (59%) have had adult children living with them for more than a year; over 1 in 5 (23%) have had adult children living with them for more than five years. On average, these parents say the longest period of time they have had their adult children living with them is 4.5 years. Parents expect their kids to help them financially during retirement: Almost a quarter of parents saving for retirement (23%) expect their children to provide financial support for them after they retire. Millennial parents are most likely to say this (44% vs. 25% of Generation X parents and 5% of baby boomer parents), despite saving more than parents from other generations.

So where is the money going..

Many parents of children 18 and older are paying or have paid for their adult children’s basic living costs, including groceries (56%), health insurance (40%) and rent or housing outside the family home (21%). Some parents are also covering or have covered their adult child’s cell phone bill (39%) and car insurance (34%). But it’s important for parents — especially those who are behind in saving for retirement — to note that those same dollars could significantly grow their nest eggs over time. In addition to these living costs, some parents of children 18 and older are paying or have paid for other expenses, such as clothing (32%), entertainment (20%), an allowance (10%) or a car loan (10%).

So, how long can your adult children be expected to interrupt your golden years? According to Nerd Wallet, 1 in 5 households surveyed said their adult children lived with them for more than half a decade.

Frankly, we continue to be shocked that all of those kids out there with $250,000 Art and Anthropology degrees are finding it difficult to land their dream jobs...