I really like this story, unfortunately not very known and strangely made by Ralph Nelson for Australia audiences. Only the late Karen Black and Keir Dullea as leads from USA.
This film talks of the difficulties encountered by a couple with their mentally retarded child. A typical topic for a TV movie, already spoken about for sure. But that doesn't matter, the approach may be different from a feature to another. For instance it is shown here the impact that fact could have on the professional skill of the husband. You see he is a sergeant aboard a submarine. And the scene where one of his superior asks him about his retarded child and the difficulties that occurred, this sequence is quite disturbing, because you may think that could also have bad consequences on the husband's - Dullea - military duty, the way he manages the stress aboard the submarine, with all the responsibilities that means.
And this TV movie is also a little expose about submarine crews. For instance, you learn that if one of the men aboard had some problems with the underwater life, they can ask for a surface affectation, without any disturbances on their career.