Can anyone tell me if this can be done? From scouring the internet and the Apple faq's I'm still not sure....

OK,this gets kind of confusing. I have had the same 146 songs and 10 videos on my ipod nano for probably a year or two. For the first time in quite awhile I downloaded some new songs on Itunes last nite. Somehow in the process I accidentally deleted everything I had on there prior and now I only have the songs from last nite...

Well as it turns out my daughter informed me today that she hasnt used her ipod in sometime because the last time she tried to download something she accidentally put my 146 songs/videos on her ipod and she put her ipod in her drawer and never bothered to do anything about it.So now she has all the old songs/videos I had plus the ones I downloaded onto it today. I guess I could just use her ipod but I would rather transfer all that over to mine and let her start using hers again. Regardless of what I have tried the Itunes program will not let me transfer her library over to mine. Can this not be done??All of these songs and ipod accounts are just on this computer I am on now. ARGHHHHHHHHHH