We're friends too
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Actually, I know exactly what you mean. Mine won't really sleep outside her crib either. It's really really frustrating, as I can't leave the house until the second nap is over.
What you might want to try that has worked for others is taking a familiar bedtime object with you...a sheet that you always use, something with the same kind of surface your lo usually sleeps on, a stuffed animal, lovey, etc. You want to try the best you can to duplicate the kind of environment she's use to sleeping in. Obviously it won't be exact, but close is good enough. Use the same routine you normally use to get her to sleep, as close as you can. Also, you can try getting her use to sleeping in her travel seat or whatever you'll be using during naptime at home, so she gets use to the feel of it.
Also, I'm not sure any lo sleeps really well outside the normal sleep environment unless they're really use to it. You'll get as far as getting her to sleep, but go expecting a short nap. There's just too many new things to see!
Hope one of these ideas help!
*HUGS*
Sonya =P