<human>: Could you distill the essence of the text into 1-3 sentences?

I have two roommates in a nice apartment.  The building is a diverse mix of families and college students.  We three are grad students, all studying some form of medical science.  When we first moved in in August, our sweet elderly neighbor next door smoked.  She mostly smoked outside, but every now and then, we'd smell it as it crept through the vents.  It got to the point where I couldn't leave clothes sitting out or leave my closet door open because I'd come home to them smelling like smoke (This was not an ideal incentive to keep my clothes put away).  
Our landlord, one of the 5 nicest people I know, had a talk with her, asking her to smoke only outside, even though she is technically allowed to smoke in her own apartment.  A couple weeks later, she was hospitalized for a serious cardiovascular incident.  I'm no doctor (yet! LOLOLO---  sorry..... :-/ ) but I'm going to guess smoking played a role.  Sadly, she succumbed to her illness.  While we lost a friendly neighbor, we gained several months of fresh air.  
Until recently.  
A relative of hers moved in and has started smoking.  We mentioned it to our landlord again, and I think he spoke to the occupant, but nothing's changed yet.  The roommate whose bedroom wall is adjacent to her apartment gets it the worst - his bedsheets smell of cigarettes and he may try to move elsewhere next year.  He says on days when he has to spend hours studying in his room, he feels like he smokes half a pack secondhandedly.
  
So, Reddit, do you know of any reliable methods for keeping the stink down?  We changed the filters on our vents, btw.  Of course, I'm in favor of smoking cessation for public health.  If someone makes the choice to smoke, fine, but that right ends at my nostrils.
<bot>: We have a smokin neighbor, but not in the attractive sense (... scents).  How do we keep our place from gettin that stank?