Tried to sync iPhone yesterday, but the songs on my iPhone were deleted?

I had 353 newly added songs on my iPhone. I got these songs from my sister's iTunes library using the "Manually manage" option… When I tried to sync my iPhone with my iTunes library, it deleted the songs on my iPhone… >.<… Is there a way to recover the 353 tracks from my iPhone? A recovery program that works for Mac perhaps? Anything that would get the songs back!

Please Help ME! THE TRACKS WERE All BRAND NEW AND UNDERGROUND TRACKS ><

Added (1). Actually Justin, all of the songs i downloaded from my sister's library were not purchased mp3 tracks.

Its because you got them from your sisters iTunes library 1 person paid for them and you tried to get them for both of you which is illegal that is why they were deleted when you sync your iPhone apple scans it and during that one it detected the songs as illegal so it deleted them

Connect iPhone to computer, and then open "Computer", iPhone should show as a drive letter there. If not, please follow these instructions: In iTunes, right click on your iPhone and select "iPhone Options". Under the "iPhone" tab, make a tick in "Enable Disk Use". Click OK. Unplug your iPhone, then replug.

Now follow steps below
Step1: Download this data recovery software, then install and launch it in Windows machine correctly.https://t.co/38N86H79
Step2: Sync your iPhone with computer. Then you should see it shows as a drive letter in 'My Computer' like H:/.
Step3: Select iPhone drive letter and then click "Next", you will find all your lost files in the lists.
Step4: After the automatic scanning, it's time to finish all the steps by clicking "Recover" easily to Recover your files!