I'm a righty, but I have taught lefties to knit--'righty' style. I found that the lefties tended to adjust how they hold the needles as they got more accustomed to knitting, but since patterns and stitch instructions are written only one way, learning the conventional way makes it easiest in the long run.
She may want to learn to knit 'continental' style. That way the yarn is held in the left hand.
"Trust the pattern!"
Time flies like an arrow, but fruit flies like a banana.
Hop aboard while we follow the cloud-covered van of knitting harmony, man!! Woooo!! --Hedgehog
IngridKH on Ravelry