LICE REMOVAL!?

I’m 22 weeks pregnant and just found out that my little sister (who’s been staying with us for a month already) has lice 😩😖 I’m the only other one in the house with long hair. I need to know how to get rid of these ASAP! I won’t know until tomorrow morning if I have them but my sister does for sure. I’m trying not to stress over this but with all the other things that have happened this past week, this just seemed to push me over the edge. I bawled my eyes out for an hour straight. Any suggestions on products or what I should do to get rid of these things?