Keeping up appearances was terribly important back then.

That's the catch. The son is a homosexual and rather than risk exposure (which would be a sign of failure for the mother in her capacity as well as moral failure of the family), they opt to send him to a clinic once visited by Jung and Freud (during their lectures at Clark University).

The family resides in Illinois which was notorious in its treatment of homosexuals - castrating those for consensual sex as well as first degree sodomy.