"Full-time pay, part-time work!" Who wouldn't want a job like that? What employer would be insane enough to offer it?

Yet for those of us with school-age children who have held on to the nannies/sitters we hired when our kids were babies, that's in effect just what we do.

"The peace of mind premium" is what I call it. The price of knowing that when you are working, your children have that consistent, loving, completely trustworthy presence at home. Someone you don't have to worry about, who will be there when they are sick or have a holiday from school or need chauffeuring around to activities in the afternoon, on days when you can't be there because you must be at work.

It's an expensive proposition, for sure, a luxury even. But then these are your kids you're talking about. So you try to make it as financially viable as possible. You add new responsibilities and chores to the job description to fill in the time: more housekeeping duties, errands, meal preparation, things that are more valuable to you than they are to the kids.

You justify it in economic terms. When the kids were preschoolers and she was working virtually nonstop from 7:30 a.m. to 6:30 p.m., it was an impossibly long day at relatively low pay. Now her overall hours are shorter and her wages are fairer. You can't cut her salary because she needs the money to pay her mortgage, her bills, the babysitter for her own young child. If you did, if you said, "We're going to pay you less because we need you less," she'd find another job.

Still, I wonder. Our nanny, who was been with us for almost seven years, since right after my second son was born, can go to college full time, taking day and night classes, while she's also working for us full time. She has the time to do it because I can't possibly give her enough to do to fill all the hours. And there's no purpose in making her sit in an empty house with nothing to do simply because we're paying her to be there.

Friends have taken a different approach. They've given up the full-time sitter for au pairs, job-sharing arrangements, a hodgepodge of childcare situations that may involve after-school programs and the kindness of relatives and stay-at-home moms. I tried the latter once, when our nanny was on maternity leave last year. The increased stress level for me in having to rush home before the after-school program closed or cobbling together various arrangements was too much to bear.

So I fork out the full-time salary every week--and a full-time Christmas bonus this week--and I try not to count the hours she's actually working. I know my kids are well taken care of and I can go about my professional business with peace of mind. It's at a premium, yes. Part of it comes out of the college fund or the vacation budget, but I'm lucky I can afford it. Because that's the way it has to be for now.

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