Let me think . . .
Having practiced pediatrics
for over 20 years, i can say that every culture I have encountered has a special way of talking baby-talk to babies, toddler-talk to toddlers, and so on.
It is normal for humans to speak to preschoolers, grade-schoolers, middle-schoolers, teenagers, and college students all in manners different from one another. It would sound very strange if people did not do that!