Creating impossible goals for children

Hello! I have a question about applying the model to my work with children. I am a speech language pathologist and I help toddlers who aren’t talking learn to talk.

I’ve been playing around with setting impossible goals (my client will say 10 words after three sessions with me), things I never would have considered saying before in such a short time frame. And I love the ideas/actions it is producing in me. As long as I take responsibility for the outcome, do you see any problem with setting goals like this for a child? Can you point me to any specific resources about applying the model as I work with children and their parents? Thank you!