Here ya go:

1. Shane does something. Being a better Big Brother than I am, Don takes the rap and goes off to the local place of durance vile.

2. Shane, in a fit of alcoholic remorse, joins the Trappists and ends up in Madagascar.

3. Meanwhile, back in Blind River, someone else realizes (or, being Canadian, realises) that with Don in the hoosegow and Shane off to the cloister the road to steal Shane's identity is wide open (as is the beer cooler and Don's bank account).

4. Shane is kicked out of the Trappists and sent back to Canada, but misses his plane and ends up in Amsterdam. Eventually, the Canadian Consulate arranges a trip home for him on an icebreaker and to pay his way back he's put to cleaning the heads.

5. Someone else pretends to be Shanetta, Shane's twin sister. But IWTATBM confesses that was her/him. But another Shanetta appears, one with a PhD in Computational Physics (or so she claims).

6. Shane's icebreaker is re-routed to the Boothia Peninsula on a rescue mission, which does not make Shane happy.

7. Someone posts as Don McBride, claiming that Shane really is his brother. Immediately thereafter, someone claiming to be Shane posts that Don posted because he (Shane) "ast" him to.

So we have Don, Shane, Shane, and Shanetta. And I think it's time for a bunch of DNA tests.