Mother in law

In a bit of a pickle. My husbands mom is a heavy heavy smoker. I personally have never seen the inside of her home as my husband will not allow it. I’ve been told she is a bit of a hoarder and smokes in the home. When she comes over for visits, the scent of smoke is VERY VERY strong. I do not want her holding my child after he/she is born as I am concerned about her cleanliness and the health of my baby. How can I talk to my husband without offending him?