Yes, I definitely would let her sew. My almost 4 year old grandson sews on my lap and he has learned to pin and use scissors. I keep my rotary cutters and seam rippers on a skyhook, but he does enjoy playing with my older ruler. His favorite thing to do when he comes over is sew. I guide the fabric through the machine and he rests his little hands on top of mine. He loves fabric and sewing machines. I set him up with some fabric in a hoop and he practices hand sewing that I later take out and replace with another piece. Have fun and enjoy each others company and closeness.