I have an eight year old daughter who picks up my violin often and plays left handed. I've tried to get her to play right handed, but it's so unnatural for her that she just puts it down. And then a few hours later she's playing again and doesn't even realize she's playing left handed.
I had thought, before doing a google search and seeing this post, that lefties had to play right handed. But I see that is not the case. She is so obviously left-handed in playing the violin that it seems I either chose to let her play left handed or she probably won't be interested in it.
Now the search for a teacher who's willing to teach a leftie!