My MIL just told me over the phone that my SIL (my BIL's wife, who my MIL doesn't like) has only 'gone and gotten herself pregnant!!' (cue exasperated sigh from MIL). My response 'well I'm sure she didn't do it by herself' 
My MIL does hold quite old-fashioned views, but this has just really annoyed me! AIBU?