Cigarette smoke

Hi mamas. My husband and I currently live with my mother with our 2 month old due to financial reasons. My mom’s step mom will be here tomorrow and supposedly staying until January for the holidays since her husband recently passed away. Anyway, she smokes like a freight train and this has me worrying about the well being of our baby... my mom said she will smoke outside but if she smokes as much as she says she does, it will still linger in the house and on her. Will this effect our baby at all? I’m just being a huge Mama bear right now and I don’t want the smoke to interfere with him 😕 advice? Opinions?