Not so fast, "obviously".

I believe that "neolocal" households are unique, mostly, to post middle age Western Europe. And the 1950s are anomalous within that time scale.

Otherwise we see patri- or matri local multi generational households in which adulthood is not correlated with setting up a new household at all. You would marry someone and the move into their parents house. Sure you would start having children, but there isn't the same leaving adolescence thing.