husband and sister drama

so I'm currently pregnant with my second son I'm 26 weeks and me and my husband are planning on who we want coming to the hospital since both our families don't get along it's a long story. Anyways I told my husband his sister wasn't able to come she hasn't seen my oldest in 3 years due to her drugs and her taking my son from me and I had to get him back thru police she still hasn't change and always tries to fight me. my husband doesn't get along with my sister because of her damn mouth I'll be on the phone with her and she'll call him a dead beat because be was late for my first son's birth because he was in college. And she constantly saying he's a bum I'll f him up etc. And this has been going on for years! I just want us to be comfortable so I told my sister how we felt she started going crazy saying she's coming to fight him and he's a dick and keep her name out his mouth he's a walking to much etc she's super immature and she's coming weather he likes it or not fuck him and call the police she'll start drama there. like I don't want her stressing me out but she is and I'm fed u. The doctor told me I can make a list of people and give it to the front desk which is only 2 people. But she's telling me she's finding a way to get in. Me and my sister always fight and argue we got into a huge fight before I was pregnant and she would call me so many hurtful things and I cut her out. I was adopted by her mom so she's technically my adopted sso when i found out i was pregnant sje tried to talk to me kissing my ass when she gave me so much problems. telling me to leave my husband chose him or herister. this is the drama I don't want I'm doing it so I'm not stressed and my 5 yr old will be there and he sees her always acting like this. I need some advice