If you rooted her, did you also flash her recovery? if so, the alternate recoveries (SPR and CWM) will auto block the OTA install. However, if you can navigate through the file system, you should be able to find the file and apply it manually - you may have to go digging around somewhere though, b/c I think the new OTA downloads do not just download to the root of the SDCard, they pick a more subtle location, like perhaps in the temp folder, or somewhere else.