We are not our parents and we are not our children

I once read that if you fill a child's cup (their mind), then they will not have
room for additional "potentially bad" things. In other words, teach your
children all they need to know.

I think a more realistic approach is this:

You fill a child's cup partially (the amount will vary by parents)
They, as people, and experiences in their lives will fill it the rest of the way.
Why we are human, not perfect, not our parents, and we are not them determined
by what they fill it with. It may be the same "liquid" we used, it may be different, it may mix well, it may not. They may pour some out and add something new. Things can also
be complicated by the fact that the cup may be cracked from the start or crack
in response to what it added.

Just a thought.