You hate leaving your kids.

It’s not that you don’t want a break from them sometimes, because you need that for your sanity. And it’s not the pitiful way they cry, ripping your heart out, even though you know they’ll be playing 10 seconds after you’re through the door.

No, you hate leaving your kids because of that nagging little voice in the back of your head. It says that nobody can care for them the way you do.

In the new novel “Substitute Me” by Lori L. Tharpsc (2010, Atria. $15 / $17 Canada. 343 pages + extras), a working mother finds the perfect nanny for her son. But perfection comes with a price.

Zora Anderson’s family thought she’d kicked around enough, and that it was time for her to get her life on track. Problem was, Zora had no idea what she wanted to do. She was nearing 30 years old, had dropped out of college, gone to culinary school in Detroit, nannied in Europe, and was now unemployed.

So, without telling her family of her plans, Zora answered a personals ad of a White couple in Brooklyn, who were looking for someone to care for their son. Zora had loved being a nanny in France. Why not do in New York?

In the back of her mind, though, something wasn’t quite right. Zora was well aware of how it might look: a Black woman caring for a White baby? She wasn’t anybody’s mammy but racial history seemed to nag at her just the same.

Kate Carter had loved staying home with little Oliver, but she was looking forward to returning to work. Jacobs & Zimbalist wouldn’t hold her job forever, and although she knew there’d be long hours ahead, she was ready for some adult company. An energetic, smart woman like her couldn’t thrive on baby talk and mommy and me events.

Brad Carter liked to think of himself as a progressive guy who saw each person as an individual, so when his wife, Kate, hired a Black woman as a nanny, he was aware that there might be some discomfort in the situation. But as Zora began to fit into the routine and become a valued member of his and Kate’s lives, Brad began to see things differently.

As it turns out, discomfort was only the start …

Author Lori L. Tharps, who has written two non-fiction books and dozens of magazine articles, takes a crack at fiction-writing with “Substitute Me,” and for a debut novel, it ain’t bad.

Although the story tends to drag a little now and again, Tharps constantly tweaks her readers with several plot lines that make us ponder our beliefs on race, heritage, and privilege. There’s also some predictability here; not enough to ruin the plot, but enough that you’ll see what’s coming, and you’ll (sheepishly) find yourself wondering why the characters can’t see it, too.