This is a ballsy episode with a heartbreaking theme, but it isn't the tearjerker it should have been.
First up, congratulations to the writers for going through with a storyline like this. Although the character of Seth was created solely for this episode, the idea of a young life being snatched away is very poignant, and for once, gives the audience something to think about beyond who will be leading the goodnights this week.
Each character reacts differently to Seth's illness. John-boy goes quiet and awkward, while Jason is in total denial and doesn't even want to see his friend. For me this was a missed opportunity. Showing Jason and Seth coming to terms with his illness together would have made this a real bullet of an episode, but instead Jason mopes in his room while Seth largely carries on as if nothing's happened. Great performances from both Richard and Jon though.
I didn't agree with Seth's mum's approach. She just wanted to lock him in his room and watch him die. The way she turned against Olivia so suddenly was bizarre, though Olivia could have helped both of them by telling her what had happened to Jim Bob's twin. In the end, Seth's dad comes home and they all move away. Considering the subject matter, it's a bit of a soft ending.
I note the guest actor playing Seth was quite a well-known actor at the time. Nice-looking bloke too. Apparently he went on to direct 'A Beautiful Mind' and 'The Da Vinci Code'. Gosh!