Opinions please!

Me and my husband and our kids( 11 y/o and 6 months baby) are going to the Dominican Republic on vacation for the holidays . We are originally from there. We are visiting families and also staying at a resort for a couple days with the kids.

Here is the reason for my post. He’s inviting his female friend (who lives there) to come with us to “watch the kids” without even asking me first and I’m not okay with that. I’ve seen her A couple of times but don’t consider her my friend. I might sound insecure but she’s about my age and she pretty ( early 30s) I’m not comfortable with that. I told him he should’ve asked me first and also I don’t need a babysitter at the resort I’ll take care of my kids. It’s a family vacation not a honey moon plus I’m not planning on getting drunk when I know he will. One of us needs to be sober in case of an emergency and of course that person is me. I just told him that and he didn’t say anything but this is the second time he brings that up about bringing her with us. If he keeps Insisting then I’ll tell him that I won’t go to the resort.