Am I overreacting? Husband smoking weed

First off I just want to preface this story that weed is legal where we live so it’s not a question of if it’s illegal thanks.

So I’ve been with my husband 7 years married now for two. We have a toddler and a baby on the way. When we met he used to be a smoker both of cigarettes and also weed. I expressed that I didn’t care for the cigarettes because of the smell that lingers everywhere but didn’t mind the weed if he just didn’t do it around me. He gave up cigarettes and not weed. About a year later I ended up smoking weed with him to try to combat headaches and it worked and I liked it so we would occasionally smoke together and it was fun. After a little while we decided to start TTC so I cut it out completely and did not go back. It took a couple of years but I finally got pregnant and now we have our beautiful daughter and are pregnant again. He gave it up when our daughter was born but took it back up a few months later I agreed that it was okay as long as it was out of the house and he wasn’t around her smelling like it. So he would do it after she was asleep and shower and come to bed.

Over the past few months he has suddenly taken up smoking multiple times a day and even when he has our daughter. He doesn’t smoke in front of her but will leave her to play, smoke outside and then come back in smelling terribly of weed. I have repeatedly asked him to stop but it seems to only be getting worse. He thinks he is doing nothing wrong because according to him “it’s not in front of her so she doesn’t even know” but now especially being pregnant I don’t want her around it or myself. He thinks I’m overreacting and he refuses to quit so I’m at a loss.

Sorry this was so long, if anyone has any ideas or advice please I could use some help.