Traveling with unreliable iPhone4

Hi All,
Hope I'm posting in the right place...I'm sure you'll tell me if I'm not. I'm planning to take a road trip with my kids. My daughter and I both have iPhone4s and while I've had no issues with mine, my daughter's freezes or resets itself regularly - both issues can be fixed with connecting to the home computer/itunes or hard-resetting and connecting to itunes.

My question is, without taking my desktop computer, how do I assure her (you know how teens are without their phone working-NOT fun) that if she has a problem on vacation we can restore her phone? We are going to a remote location without an Apple store within 4 hours *gasp.* I can take a laptop but is there a way to have the same itunes info on it as is on my desktop without moving my library to it?

Thanks, Mac-Smarties, in advance for your help!
~Shine

Can you take it to the Apple Store before you go?

Sure, copy your iTunes library to it instead of moving it.

Schweb - I could take it to the Apple store but they've already replaced one for her that completely stopped working. She's one of those people that is technology doesn't like...that's why we got her an iPhone! Thought she wouldn't have problems...she's had problems with two since May 1st!

Bobtomay - can you give me a link or steps to accomplish a copy of iTunes to my laptop. And does it matter that it's a pc - I haven's saved up enough for the MBC I want, yet.

Has she gotten it wet. My friends iphone 4 got wet and it does that now.

Turn on Homesharing in iTunes on both computers. I keep 2 Macs and a win7 machine synced with it.

Link.

@rabbitjetta- I don't think so, but she's a teen, so anything's possible.

@bobtomay- Thank you!