Did you actually go to your son's library & delete things, or did you just go thru LW's tools > options & stop sharing some folders? Unless you deleted the files then they should still be there...just not shared & maybe not showing up in his library.

Use your computer's search to look for some of the file names...see whether they're still around

If you open LW & then go tools > options > saving, you'll see the path to the folder with your saved files. Do the same in your son's LW & you'll see the path to his saved folder. You can find those folders on your computer & then copy & paste from one to the other. Or, if the files haven't actually been deleted, you can add files back into your son's LW library by adding the folder(s) for sharing. Again, this can be done from LW's tools > options.

If you tell us which version of LW you're using, we can probably help you a bit more

I am using limewire 4.16. When I deleted them, I went into options then share folders then the screen that says sharing extension I clicked off all the boxes so that there were no check marks. Thats when they all disappeared.

If you didn't actually delete the files from within LW's options, or from shared/saved folders outside of LW then the files should still be around. Just choosing not to share something won't delete it...just means that the files won't show up in LW's library.

Did you use your computer's search to look for some of the file names?

Have a look at this thread - there's info about the location of saved & shared folders in the newer versions of LW. Since you didn't tell us which 4.16 version you're using, I'm not sure where the saved & shared folders will be located. But that info's in the thread below...find those folders on your computer & see whether your son's music's all there.
If you've updated LW and can't find your downloads!