Hi there,
First of all let me say that I`m no expert on this !
Well certainly not at playing the violin anyway - I guess though that as I`m over 40 and born a "leftie" I`m pretty expert at being left handed !!!!
As a child I learned to play the violin - the right handed way and as we live very much in a right handed world us "lefties" are very good at adapting you know!
I would suggest they learn the right handed way.
I only played the violin for about 4 years - didn`t really take to it not because it was too hard as I was left handed but rather that I really wanted to play a wind instrument and the violin came a very poor second in my eyes at the time !!
Good luck to your youngster whichever "handed" they choose !
Sue