Trying to remember this very interesting series.
It began in the late 60's I think by showing about 25 kids, there lives, family, background etc. They re-visit these people every 7 years to see what's happened to them. It's called ??? 7, ??? 14, ??? 21, ??? 28, ??? 35 and they may have done 42 by now.
Great stuff but I've forgotten the name so HELP !