Jennifer Warthan at The Cotton Wife has a too-cute series of photos showing her son <5? imitating his father as he works on farm machinery.
There are some occupations, farming and storekeeping for two, where the offspring can learn at the knees of their parents. There must be some life lessons in such learning, I'm not sure what, but there must be. Of course in the days of the one earner family and the stay at home homemaker, girls learned at the knees of their mothers, but we don't, or I don't at least, grow as sentimental over those life lessons.