Today, many languages have the following in common:
-They came from nomadic pastoral people.
-Old languages developed and evolved into new languages.
-They have many cognates in common.
-One-third of the world's language come from a single language family.
-They developed in tidal waves.

Old languages developed and evolved into new languages

nobody knows everything, but parents are normally more experienced than their children based off of worldly experience despite the fact that a child might think that they know better than their parent in any given situation this might just be caused by ignorance and lack of experience.