Awesome!!!
I still can't get my daughter (also autistic, but 7 1/2) to pay much attention to my basses. She used to sometimes slap the strings a few times and say "Daddy play Face," but now she pretty much ignores the basses completely. I did notice that she had messed with my EQ sliders though.
She's also getting the hang of singing together, and sometimes in harmony!
Some day soon I'll try to snap a pic of her holding one of my basses. I'll have to be lightning fast with the camera though.
Congrats, Dad, from someone who knows!