Two Questions

Can my birth plan include that I only want my husband and sister in the room with me while I'm delivering?

And am I really that bad of a person for wanting my sister there but nobody else? Like my MIL... For one she's done a lot of bad things. Stole 700 dollars from her son, had both me and my husband at risk because she was growing marijuana and got caught (while we were living there, but we didn't know what was going on, we don't live there now). And for two, my sister and I are super close. Closer than my mother. We were practically joined at the hip growing up. There's not even a two year difference between us. My sister already said she'll take off work when I call her and tell her I'm in labor, which makes me happy. But I don't want my MIL in the delivery room because I'm not close to her. My husband gets irritated with her and she tends to say stupid things that piss him off. And the last thing I need is someone I'm not comfortable with seeing my vagina, and then my husband getting upset with her because she opens her mouth, which will be a whole mess in itself. I'm being induced in 12 days if he doesn't come on his own, so I'm out of time to really get this figured out.