FB question..help please!

Andrea 👼🏽👼🏽🌈🎀

My SOs sister who i don’t know too well bc he wasn’t raised with that family will sometimes share pictures of our daughter that I tag him in on FB. And idk who she’s friends with but I don’t want my daughter on her page for all to see. So how do i get that share button off of my posts before I post them? What do I need to go to? Bc I know the share option can be removed bc I’ve seen lots of people who only have the Like button and Comment button and people will say “make it shareable so I can share too” but idk how to do it. Thanks for your help laides!