I respectfully disagree. I think it is common for children to rebel a bit against their parents' values -- and they often gravitate to the values held by their grandparents. See the book "The Fourth Turning" for interesting generational studies of America.
Your point is well taken - kids are naturally rebellious as they become increasingly independent.
I should have been a little more clear - I think its generally true that adults tend to mimic their parents' values.