jmar
Nexican
If she wasn't such a light sleeper I would have already.
Unfortunately it would be pretty hard to do without her noticing it since unlocking the bootloader would wipe it, which she would notice. I've always said "better to ask forgiveness then permission" though.
I think you can fastboot boot recovery and nandroid her setup, then save all photos and nandroid to the computer, unlock, flash recovery, root, transfer files back to phone, nandroid back, then reroot if need be. She'd never know!

BTW, please ask Scary Alien if this is possible. I am freestyling but I think it is possible.
jmar
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I thought I had completely screwed up but it is sorta well now. She has an Optimus S I think her next phone will be either my EVO LTE or (shudder to think it) an Iphone. My next phone will be a nexus