Like a cousin who...

Which are correct:

1) He is like a cousin who makes everybody unhappy because he has to go away for a long time.
2) He is like a cousin who has to go away for a long time, which makes everybody unhappy.
3) He is like a cousin who has to go away for a long time, and that makes everybody unhappy.
4) He is like a cousin who nobody wants to see go away for a long time but who has to.

They are all supposed to mean the same thing.

Doesn't '1' imply that he is making everybody sad deliberately?
In '2' and '3', the final part is supposed to be part of the defining clause. They are supposed to define the kind of 'cousin' we are talking about.

Gratefully,
Navi.