We've all been there—a friend comes to you in child care desperation, and asks if you can recommend a sitter or if they can hire your own babysitter or nanny "just this once." They promise not to steal her away, but you're hesitant and protective of your hard-won resource. The answer most parents give to the question of "Can I share or borrow your babysitter?" is usually a clear and unequivocal "No."

Why? Well, the common feeling is that you only have a certain amount of control over your child care situation anyway—babysitters leave or graduate from college or get married, etc.—and eventually, you'll need to make alternate plans. So while it's working, people are protective, and think "Don't even consider talking to my sitter!"

This urgent need for available, high-quality, and trustworthy babysitters and nannies is one of the biggest reasons we started Care.com. Most people are still afraid, however, that even with great resources, sharing their fantastic child care provider is going to bring them back to square one all over again.

My advice is to handle those tough conversations with friends and neighbors by weighing the risk and by asking yourself the following questions:

• Who's asking for the help?
  Gauge how well you know the person, the strength of your relationship with them, and also what their regular child care situation is. Are they panicking because they're in a desperate, emergency scenario? Or, are they probing because they're looking to hire someone regular, and wouldn't regret sacrificing your friendship for a great sitter.

• How much help do they need?
  Gauge the likelihood of this person taking up all of your sitter's free time, leaving none for watching your own kids. If you've hired this sitter for two days a week and your friend only needs the occasional Saturday, then it's probably fine. However, if your nanny is with you full-time (like mine was!) and your friend needs a few weekday evenings each week, it's probably not a good idea to share your sitter.

• How much work does your sitter need?
  Gauge your sitter's own needs. Do you know how much work and how many clients they currently have, versus how much or how many they might like to have? Again, if you're only hiring your sitter every other Thursday while you have book club, and your sitter would like to work 4 nights a week, then she may leave you anyway if she's not making enough to meet her income needs. But, always use caution when acting as your sitter's personal PR assistant!

• Is there something (or someone) else you can recommend?
  In general, it's OK to be cautious and to diplomatically decline to introduce the person to your sitter. Say, "Well, my sitter is really busy, but I can ask her if she has any friends she can recommend." You can also offer to refer them to other moms who may be able to recommend a sitter or nanny, or you can always refer them to Care.com!

• Understand that you don't "own" your sitter.
  You may find yourself in a situation where your sitter needs more money, or more hours, etc. anyway. Babysitters by nature usually have half a dozen clients, where a nanny may only have one or two. Like they say in sports, "The best offense is a good defense." Make sure your babysitter or nanny is happy, and don't take it too personally if they do leave you for any reason, be it for another family or for an all-around better opportunity, like an educational, career, or geographic change. Knowing your sitter's needs up front—and trying to help her meet them!—will help ensure a long term relationship, and lessen the likelihood of her being "poached" by another family.

Remember, too, that most people poach sitters unwittingly: they don't think of it as stealing, but they may offer more money, more hours, may be a better personality fit for the sitter, or may need more help, therefore eating up all your sitter's free time (leaving less—if any—for you.)

Do you have a story or tips on babysitter poaching or nanny napping? Share it with the Care.com community by posting a comment!