I was Hasbro's only US based prototype doll hair rooter for many years, during the late '80s into the 90's and early 2000's. I rooted many hundreds, maybe thousands of prototype ponies during my time there - and beyond, as I left to freelance and continued to work for them. My wife handpainted the cutie marks on the prototypes.
My daughter, Mar, who watched my wife and I rooting & painting ponies in our studio, decided she wanted to get into the fun so at 9 years old she conceived, designed and named a pony, picking the hair colors from my stock and designing a cutie mark. I thought the lead designer at Hasbro would get a kick out of seeing this, so I brought the drawing in. The designer was so taken with it that she had us make a prototype from Mar's drawings. It went into the Funlab child testing and emerged as the #1 tested pony. This pony, which my daughter conceived, designed and named is Rainbow Dash.