My son is 20 months old, and an active child. He listens when I call his name, and we have some non-verbal communication. But he doesn't understand what I'm saying to him. Whenever I say, "Come to mama," he doesn't understand me, but when I say it while holding out my hand to come he'll come.
The only thing he understands is when I ask him to give me a hug like, "Huggiee," he will give me a hug. But he doesn't understand anything I ask him verbally.
What should I do in this case?