my parents used to call me "doctor doolitle" when i was little because i was able to "charm" animals. Even the animals that hate everyone... i think it depends on the individual, my brother was not so good with animals and was too "active".
HOWEVER, if I were a breeder and a parent comes and says "i have a gentle child" i would still think twice, because people lie. I would think that if a breeder were to place a pup in a home with a child they should conduct an interview of the whole family. Have the whole family there and see how they interact, how the kids react with the pup.. ect.... just my thoughts.
Yorkies/ dogs in general offer something very positive to the growth of a child. Responsibility, companionship, ect...
One of my preschool kids has a yorkie/dachsund mix and it is TEENY. . . But he is such a trooper... he scampers around after the girls ... he refused to walk on the leash with the mom, but would RUN on the leash with the kids, go figure