What to Do About Smell Of Narcotics?

I live in a semi-detached townhouse with my parents. I have a lot of medical issues due to an autoimmune disease. One issue being severe migraines that can be brought on by bright lights, loud noise and strong scents. We get along well with our neighbor who is an older woman. Her two grandsons and toddler great grandson moved in. Her younger grandson smoked A LOT of weed. However, I grew up smelling weed and this smells like its mixed with other substances and seeps through the vents and walls. He smokes outside when the baby is home but it still comes over to my home and makes me really sick. Any advice on what I can do? I don't want to ruin the good neighbor relationship but I literally get sick every night now for around an hour until it clears. My headache lasts a while afterwards.