Need some opinions

My daughter is 3 months next month. We are taking our oldest to a water park for her 9th birthday, The Dr recommend not taking the LO in the water etc and we were just going to take her and not put her in. My mom has offered to keep her over night (which LO has never spent the night anywhere else) is probably loose my mind! But my mom does smoke An has smoked for a long time in her home, she has just now stopped smoking inside. I know it’s still there in the house obviously My LO has never been around smoke. What would you do?