Ming from Agents of Speech says parents of non-verbal children should focus on what the child wants, not just parental goals, because kids sense pressure. The key skill to unlock others is verbal imitation, but there's a prerequisite skill you need to teach first.
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We don't want to hear you say, I want my child to do X, Y and Z. What about your child's wants? They were born in this world to fulfill what you want them to do. I know you know the best for your child, right? Let me get that out of the way. You're not wrong if you're thinking, I want my child to do X, Y. I want them to talk. I want them to like assimilate and to become a part of society to habilitate them inside of this world. That's our job, right? Don't get me wrong the first part. You got to get the mindset right. If you don't get it, kids will smell it, they'll run away. All right? Whenever you try to ask your child to say something or do something, they just run off. And that's because they can feel it. Second thing is to focus on a lead domino. The one skill that if they master it will make other skills really easy. Usually speaking if your child is non verbal, that would be verbal imitation. Verbal imitation is the stepping stone to everything. How do I get to verbal imitation? I'll just like. There's another skill that you have to get the child to master before verbal imitation.