I learned to sew I was 8 and learned on my mom's 15-91. The only toy machine I sewed on belonged to a friend - my mother didn't believe in wasting money on a toy. If I were to buy a machine for a child, it would be a machine she is already familiar with, so that she knows how it works and knows how to take care of it already. Also, you said her mother knows nothing of sewing, so it would be best if you are familiar with the machine to help her when she needs it. I don't know if you can find a used machine, and to buy it new would be out of the question, then I would consider a low end Brother with multiple stitches and feet.