Grandparents rights

Okay so I'm kind of torn on this subject. I'm not sure if grandparents rights are recognized in my state, but regardless, how do you feel about them being enforced? Why or why not should grandparents have rights to this biological children? My MIL and step FIL molested my brother and sister in law. They did not however molest my husband. Along with other things that I'm not going to post because I know that topic is hard for people, do you think I am wrong for saying no to them seeing our children even though they had not touched/done anything to my husband? I need some input. If it were my parents I don't honestly know if I'd say no. I just can't even fathom someone doing the things I've been told. But my MIL keeps threatening saying when my baby is born if she doesn't get to see it she will take me to court over it. Again, not sure if it is recognized I may just be upsetting myself over nothing, but do you feel grandparents have a right to their grandchildren? I'd like to hear both side responses.