In nearly two out of three American families, both parents work but can't afford daycare. Others don't want outside help to raise the children.

Now millions of parents are what sociologists call "tag team" parents. While one parent works, the other is home with the children and vice versa.

But experts warn while it saves money, there's concern about the lack of sleep and little quality time between parents.

Studies show tag team parents are at higher risk for divorce.