Well, that's quite unfortunate. Did you tell him not to delete/replace your file? But anyways, you could just do it again. You may have done a lot the first time but you can do it again on the second, and maybe make an improvement in your next saved progress.
And just teach him not to delete someone's saved file.
It's going pretty good... except I was extremely dissapointed because while I was in the hospital my 5 year old nephew visited. I love him and all, but I let him play my new PMD game and he deleted my file! And I was almost done with the game! >_<
Well, actually, I wasn't on PC for the last few days because my bronchitis turned into bad pnemonia without me really noticing. So I've been in the hospital since around 2:00 am on Tuesday. I just got released a few hours ago actually. ' and I'm on a crapton of antibiotics. Not fun.